Question

Simplify the following algebraic expression and then find the value: 3x² - y² - z² - x² + 2y² + 4z², when x = 1, y = -2 and z = 2. 
pls answer ​

Answer 1

Answer:

when x=1,y=-2, z=2

=>. 3*1^2- (-2)^2 - (2)^2 - 1^2 +2*(-2)^2+4(2)^2

=>. 3-4-4-1+2*4+4*4

=>. 3-9+8+16

=>. 18.