Simplify the expression 5(2x - 3) - 4x + 7.
- 6x + 22
- 6x - 22
- 14x - 8
- 6x - 8 Correct answer.
Explanation
Distribute the 5 to get 10x - 15, then combine like terms: 10x - 4x = 6x and -15 + 7 = -8. The simplified result is 6x - 8.
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Distribute the 5 to get 10x - 15, then combine like terms: 10x - 4x = 6x and -15 + 7 = -8. The simplified result is 6x - 8.
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Square a first: 3 squared is 9, and 2 times 9 is 18. Then subtract 3 times 4, which is 12, so 18 - 12 = 6.
Parallel lines share the same slope but have different y-intercepts. The given line has slope 3, so y = 3x + 2 is parallel because it also has slope 3.
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Two numbers that multiply to 12 and add to -7 are -3 and -4. Therefore the quadratic factors as (x - 3)(x - 4), which expands back to the original expression.
Here a = 1, b = -4, and c = -5, so the discriminant is 16 + 20 = 36 and its square root is 6. Applying the formula gives (4 + 6)/2 = 5 and (4 - 6)/2 = -1.
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Multiply the coefficients: 2 times 3 is 6. Add exponents for each base: x has 2 + 1 = 3 and y has 1 + 3 = 4, giving 6x^3 y^4.
A y-intercept occurs where x = 0, so substitute zero to get 3y = 12 and y = 4. The point is (0, 4).
Distribute to get 5x - 10 = 3x + 8, then subtract 3x from both sides to get 2x - 10 = 8. Adding 10 gives 2x = 18, so x = 9.
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Rewrite 32 as 2^5 so the equation becomes 2^(x + 1) = 2^5. Equal bases mean equal exponents, so x + 1 = 5 and x = 4.
Set 3n + 40 less than or equal to 250, so 3n is at most 210 and n is at most 70. Since 70 fixtures cost exactly $250, that is the maximum whole number allowed.
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A quadratic has exactly one real solution when its discriminant b^2 - 4ac equals zero. Here that means k^2 - 36 = 0, so k = 6 or k = -6.
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In a linear model of the form y = mx + b, the coefficient m multiplying the variable gives the constant rate of change. Here h is hours, so 16 dollars per hour is the rate at which pay grows. The 40 is the constant added regardless of hours.
Substitute carefully, keeping the signs: 3(-4) - 2(5) = -12 - 10 = -22. A common slip is losing the negative sign on x before multiplying.
Subtract 5 from both sides to get -3x > 15, then divide by -3. Dividing an inequality by a negative number reverses the direction, giving x < -5.
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Slope equals the change in y divided by the change in x: (11 - 3)/(6 - 2) = 8/4 = 2. Keeping the subtraction in the same order for both coordinates is essential.
Distribute to get 7 - 2x + 6 = 1, then combine to 13 - 2x = 1. Subtracting 13 gives -2x = -12, so x = 6.
When multiplying powers with the same base, add the exponents: 5 + (-2) = 3, so the product is x^3. The base stays the same throughout.
Slope is the change in the vertical quantity per one-unit change in the horizontal quantity. A slope of -75 means the balance decreases by 75 dollars for each additional day. The starting balance would be the y-intercept, not the slope.
Cross-multiply to get 3(x + 4) = 5(x - 2), which expands to 3x + 12 = 5x - 10. Solving gives 22 = 2x, so x = 11, which is valid because it is neither 2 nor -4.
Let w be the width; then the length is 2w + 5. Perimeter gives 2w + 2(2w + 5) = 46, so 6w + 10 = 46 and w = 6. Checking: length 17 and width 6 give perimeter 46.
To find the inverse value, set 4x - 9 = 15 and solve: 4x = 24, so x = 6. This means 6 panels require 15 fittings under the model.
Divide each term in the numerator by 3x: 6x^3/(3x) = 2x^2 and -9x^2/(3x) = -3x. The result is 2x^2 - 3x.
The x-coordinate of the vertex is -b/(2a) = 6/2 = 3. Substituting gives 9 - 18 + 5 = -4, so the vertex is (3, -4).
Slope is (0 - (-8))/(4 - 0) = 8/4 = 2, and the y-intercept is -8, so y = 2x - 8. Substituting x = 4 confirms y = 0.
Set 12t + 5 = 41, giving 12t = 36 and t = 3. So the model reaches 41 installed units at 3 hours into the shift.
From the second equation x = y + 2. Substituting gives 3(y + 2) + 2y = 16, so 5y = 10 and y = 2, then x = 4. Both original equations are satisfied.
Factor out the common 2 to get 2(x^2 - 4), then apply the difference of squares to obtain 2(x - 2)(x + 2). Complete factorization requires factoring until no further factors remain.
Factor the denominator as (x - 4)(x + 3), so the fraction simplifies to 1/(x - 4) when x is not -3. The simplified denominator also excludes x = 4, so both values must be excluded from the original domain.
This is a downward-opening parabola with vertex at t = -b/(2a) = 25/2 = 12.5. Production rises from t = 0 up to the vertex and falls afterward, so it increases on 0 < t < 12.5.
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Multiply numerator and denominator by xy to clear the minor fractions. The numerator becomes y + x and the denominator becomes y - x, giving (x + y)/(y - x).
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