Question

4. Find the value of the expression (3x2+2xºy+5y)(3xy-7xy+4y)
when x=-1, y=-2​

Answer 1

Answer:

48

Step-by-step explanation:

Given

==>(3X^2+2XY+5Y)(3XY-7XY+4Y)

==>(3X^2+2XY+5Y)(-4XY+4Y)

given that x=-1 and y= -2

substitute these values in above equation

==>(3(-1)^2+2(-1)(-2)+5(-2)) (-4(-1)(-2)+4(-2))

[- * - = +

+ * - = -

- * + = -

+ * + = +]

(-1)^2= 1;

(-1)(-2)=2;

following the above rules the equation get solved as

==>(3(1)+2(2)+5(-2)) (-4(2)+4(-2))

==>(3+4-10) (-8-8)

==>(-3) (-16)

==>48