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1 vote
Solve for w.
21=-3/8w

1 Answer

5 votes

Answer:

w = -56

Explanation:

Solve for w:

21 = (-3 w)/8

Hint: | Reverse the equality in 21 = (-3 w)/8 in order to isolate w to the left hand side.

21 = (-3 w)/8 is equivalent to (-3 w)/8 = 21:

(-3 w)/8 = 21

Hint: | Multiply both sides by a constant to simplify the equation.

Multiply both sides of (-3 w)/8 = 21 by -8/3:

(-8 (-3) w)/(3×8) = (-8)/3×21

Hint: | Express (-8)/3×(-3)/8 as a single fraction.

(-8)/3×(-3)/8 = (-8 (-3))/(3×8):

(-8 (-3))/(3×8) w = (-8)/3×21

Hint: | Express (-8)/3×21 as a single fraction.

(-8)/3×21 = (-8×21)/3:

(-8 (-3) w)/(3×8) = (-8×21)/3

Hint: | In (-8 (-3) w)/(3×8), divide -8 in the numerator by 8 in the denominator.

(-8)/8 = (8 (-1))/8 = -1:

(-3-1 w)/3 = (-8×21)/3

Hint: | In (-(-3) w)/3, divide -3 in the numerator by 3 in the denominator.

(-3)/3 = (3 (-1))/3 = -1:

--1 w = (-8×21)/3

Hint: | Multiply all instances of -1 in -(-w).

(-1)^2 = 1:

w = (-8×21)/3

Hint: | In (-8×21)/3, divide 21 in the numerator by 3 in the denominator.

21/3 = (3×7)/3 = 7:

w = -87

Hint: | Multiply -8 and 7 together.

-8×7 = -56:

Answer: w = -56