Question

Subtract
i) $4a-2b-c$ from $-a+2b+3c$
ii) $-3x^2+7y^2-z^{2}from2x^2-5y^2-7z^2$

Answer 1

(1)

$(-a+2b+3c)-(4a-2b-c)$

$=-a+2b+3c-4a+2b+c$

$=-a-4a+2b+2b+3c+c$

$=-5a+4b+4c$

(2)

$(2x^2-5y^2-7z^2)-(-3x^2+7y^2-z^2)$

$=2x^2-5y^2-7z^2+3x^2-7y^2+z^2$

$=2x^2+3x^2-5y^2-7y^2-7z^2+z^2$

$=5x^2-12y^2-6z^2$