Question

3x squared + 4 y squared if x equal to 2 y equal 1 and Z equal -3

Answer 1

Substitute the given values of x=2, y=1 and z=-3 where applicable to find the value of the expression:

$3x^2+4y^2$

Taking the given values in consideration, then:

$\begin{gathered} 3x^2+4y^2=3(2)^2+4(1)^2 \\ =3(4)+4(1) \\ =12+4 \\ =16 \end{gathered}$

Therefore:

$x=2\wedge y=1\wedge z=-3\Rightarrow3x^2+4y^2=16$

Notice that the value of z was not used.