Question

Помогите пожалуйста!
Сроочноо!!

1. 5x^2 - 12 + 7x= x^2 + 7x
2. 3x^2 - 10x + 2= 17 - 10x
3. (x-3) (x+3) = (x-9) (2x+1)
4. 2-(4x+1) (2-x) = x^2
5. x^2 - (1-4x) (x-3) = 3

Answer 1

$5x^2-12+7x=x^2+7x \\ 4x^2-12=0 \\ x^2-3=0 \\ (x- \sqrt{3})(x+ \sqrt{3})=0 \\ x- \sqrt{3}=0;x= \sqrt{3} \\ x+ \sqrt{3}=0;x=- \sqrt{3} \\ x_1=- \sqrt{3} \\ x_2= \sqrt{3} \\ \\ 3x^2-10x+2=17-10x \\ 3x^2-15=0 \\ |:3 \\ x^2-5=0 \\ (x- \sqrt{5})(x+ \sqrt{5})=0 \\ x- \sqrt{5}=0;x= \sqrt{5} \\ x+ \sqrt{5}=0;x=- \sqrt{5} \\ x_1=- \sqrt{5} \\ x_2= \sqrt{5} \\ \\ (x-3)(x+3)=(x-9)(2x+1) \\ x^2-9=2x^2+x-18x-9 \\ x^2-17x=0 \\ x(x-17)=0 \\ x=0 \\ x-17=0;x=17 \\ x_1=0 \\ x_2=17$