Tolong dibantu ya, terimakasih

7) x = x1 - 2
x + 2 = x1
masukan x = x+2
2(x+2)² + 4(x+2) - 1 = 0
2(x²+4x+4) + 4x + 8 - 1 = 0
2x² + 8x + 8 + 4x + 7 = 0
2x² + 12x + 15 = 0
8) a² + b² = (a + b)² - 2ab
= (-(-2)/3)² - 2(-5/3)
= (4/9) + 10/3
= (4/9) + 30/9
= 34/9
9) 2x² + 3 ≤ 5x
2x² - 5x + 3 ≤ 0
(2x - 3)(x - 1) ≤ 0
1 ≤ x ≤ 3/2