Question

Please solve the underlined question thank you!

Answer 1

Explanation:

50x^2 - 72 = 0

2(25x^2 - 36) = 0

2(5x + 6)(5x - 6) = 0

5x + 6 =0; x = -6/5

5x - 6 = 0; x = 6/5

Answer

x = ± 6/5

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9x^2 + 6x = 10

Divide both sides by 9

x^2 + 2/3 x = 10/9

b/2 = 2/3 * 1/2 = 2/6 = 1/3

As you know (1/3)^2 = 1/9

so add both sides by 1/9

x^2 + 2/3 x + 1/9 = 10/9 + 1/9

(x + 1/3)^2 = 11/9

x + 1/3 = ±√11/9

x = ± √11 / 3 - 1/3

Answer:

x = ± √11 / 3 - 1/3

Answer 2

Explanation:

4

Take out a 2 to begin with.

2(25x^2 - 36) This is the difference of squares (inside the brackets). Factor.

2*(5x - 6)(5x + 6)