Hello!
Answer:
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Step-by-step explanation:
7(w + 9) = 91
First, we must multiply everything in the brackets by 7.
= 7(w) + 7(9) = 91
= 7w + 63 = 91
Now, we must solve for w. To do this, we will need to isolate it by perfoming the opposite operation on 63. Since it is +63, we'll need to subtract it from both sides of the equation.
= 7w + 63 = 91
- 63 - 63
7w = 28
Since w is being multiplied, we'll have to perform the opposite operation (which is division).
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w = 4