Question

помогите решить пожалуйста ​

Answer 1

1)

$0.6x(2x - 1)(2x + 1) + 0.3(6 + 5x)(6 - 5x) = 0.6x(4x ^{2} - 1) + 0.3(36 - 25x {}^{2} )$

2)

$36a { }^{2} - 49 + 12a = 12a(1 + 3a) - 49 = > 36a {}^{2} + 12a = 12a + 26a {}^{2} = > 36a {}^{2} = 26a {}^{2} = > 10a {}^{2} = 0 = > a = 0$

3) 1.

$36a {}^{2} - 100x {}^{2} = (6a - 10x)(6a + 10x)$

2.

${(a + 7)}^{2} - 49 = (a + 7 - 7)(a + 7 + 7) = a(a + 14)$