Solving Equations - Middle grade

What value of A makes this equation true?

A – 7 x 4 = 12

a. 20
b. 32
c. 40
d. 48

Answer : c

Explanation:
Lets solve this problem by combining like terms and then isolating the variable on one side of the equal sign as follows:

A – 28 = 12 First step was to use the order of Operations and multiply
the 7 and 4.

A – 28 + 28 = 12 + 28 Second step involves adding 28 to both sides to isolate the
Variable.

A = 40

We can check the answer by substituting 40 in the original equation and solving as follows:

40 – 7 x 4 = 12

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