Answer:
w = 7 + x
Step-by-step explanation:
The formula for the area of a rectangle is
A = lw
56 + 8x = 8w
Divide both sides by 8
w = 7 + x
That would be the commutative property

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Answer: 3.15 mm²
Step-by-step explanation:
First, we multiply the height by the base: 4.2 x 1.5 = 6.3
But, since this is a triangle, we have to divide this number by 2: 6.3 / 2 = 3.15
Hope this helps you!