Answer:
She didn't put the sign's in the proper place, it should be ( x + 3 ) ( x - 7 )
Step-by-step explanation:
( x - 3 ) ( x + 7 ) = x² + 7x - 3x - 21 = x² + 4x - 21
( x + 3 ) ( x - 7 ) = x² - 7x + 3x - 21 = x² - 4x - 21
9514 1404 393
Answer:
18/49
Step-by-step explanation:
Invert and multiply:
3/7 ÷ 1 1/6 = (3/7) ÷ (7/6)
= (3/7)×(6/7) = (3×6)/(7×7)
= 18/49
5x -2 = 63
<u> +2 = +2 (add 2 to both sides)</u>
<u>5x = 65 (your equation)</u>
5 5 (divide both sides by 5)
x = 13
Billy is 13 years old.
(check: 13 x 5 - 2 = 63
