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Can someone solve this equation please ? 3/4x + 7 = -8

User Valenterry
by
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1 Answer

4 votes

Answer:

x = -20

Explanation:

Solve for x:

(3 x)/4 + 7 = -8

Put each term in (3 x)/4 + 7 over the common denominator 4: (3 x)/4 + 7 = (3 x)/4 + 28/4:

((3 x)/4 + 28/4) = -8

(3 x)/4 + 28/4 = (3 x + 28)/4:

(1/4 (3 x + 28)) = -8

Multiply both sides of (3 x + 28)/4 = -8 by 4:

(4 (3 x + 28))/4 = -8×4

(4 (3 x + 28))/4 = 4/4×(3 x + 28) = 3 x + 28:

(3 x + 28) = -8×4

4 (-8) = -32:

3 x + 28 = -32

Subtract 28 from both sides:

3 x + (28 - 28) = -28 - 32

28 - 28 = 0:

3 x = -28 - 32

-28 - 32 = -60:

3 x = -60

Divide both sides of 3 x = -60 by 3:

(3 x)/3 = (-60)/3

3/3 = 1:

x = (-60)/3

The gcd of -60 and 3 is 3, so (-60)/3 = (3 (-20))/(3×1) = 3/3×-20 = -20:

Answer: x = -20

User Robzero
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4.7k points