9/6 = 1.5
24/1.5 = 16
triangle DEF has a primeter of 16 inches
Percent is parts out of 100 so
45%=45/100=9/20
'of' means multiply
18 =9/20 times something
multiply both sides by 20/9 to clear fraction
360/9=something
40=something
the value is 40
You can exploit the difference-of-squares identity,
<em>a</em>² - <em>b</em>² = (<em>a</em> - <em>b</em>) (<em>a</em> + <em>b</em>)
Then
101.5² - 100.5² = (101.5 - 100.5) * (101.5 + 100.5)
101.5² - 100.5² = 1 * 202
101.5² - 100.5² = 202
