Упростите выражения ( 2a + 3x )(5a-x)-(a+x)(10a-3x); (7x+1)(x-5)+(3x-2)(2x+7);

Упростим выражения:

1) (2 * a + 3 * x) * (5 * a - x) - (a + x) * (10 * a - 3 * x) = 2 * 5 * a * a - 2 * a * x + 3 * x * 5 * a - 3 * x * x - (10 * a * a - 3 * a * x + 10 * a * x - 3 * x * x) = 10 * a - 2 * a * x + 15 * a * x - 3 * x - (10 * a + 7 * a * x - 3 * x = 10 * a + 13 * a * x - 3 * x - 10 * a - 7 * a * x + 3 * x = 13 * a * x - 7 * a * x = 6 * a * x; 

2) (7 * x + 1) * (x - 5) + (3 * x - 2) * (2 * x + 7) = 7 * x + 7 * 5 * x + 1 * x - 5 + 6 * x + 3 * 7 * x - 2 * 2 * x - 14 = 7 * x + 35 * x + x - 5 + 6 * x + 21 * x - 4 * x - 14 = 13 * x + 36 * x + 17 * x - 19 = 13 * x + 53 * x - 19.