Answer:
Explanation:
49q² -70q +25 , rewrite the first two terms as squares
(7q)² -70q + 5² , compare with a² - 2ab + b² = (a-b)²
a² - 2ab + b²
(7q)² -2(7q)(5 )+ 5², because 70q = 2*35q = 2*7*5*q
We can see that a = 7q and b=5, therefore
49q² -70q +25 = (7q -5)²
We set the equation equal to 0 to find the roots
7q-5 =0, add 5 to both sides
7q =5 , divide both sides by 7
q = 5/7 ≈ 0.714