x² - 14x + 49 cm²

_____________________________

Problem

Find the area of the square whose side measures (x - 7)

Formula in finding the area of a square

side x side = area

Given

(x - 7) cm

Solution

(x - 7) (x - 7)

To multiply two binomials we can achieve its product by doing the FOIL method.

• First Term. Outer Term. Inner Term. Last Term.

The first term to the last term of multiplying x - 7 to x - 7.

• first term - multiply x and x
• outer term - multiply x (of the first parenthesis) and -7 (of the second parenthesis
• inner term - multiply -7 (of the first parenthesis) and x (of the second parenthesis)
• first term - multiply -7 (of the first parenthesis) and -7 (of the second parenthesis)

In multiplying them we're gonna get the product of:

• first term — x²
• outer term — -7x
• inner term — -7x
• last term — 49

In this case we have a “like terms” the -7x of outer term and another -7x of inner term. To simplify this equation we must combine like terms

• -7x + (-7x) = -14x

Now there is nothing else to do. Thus, the answer is x² - 14x + 49

Since we're dealing with square we have to write beside our answer which is the x² - 14x + 49 the “cm²”

Full answer: x² - 14x + 49 cm²