Question

Evaluate the polynomial when x = 3 and y = - 8
x2 + y2 + xy
​

Answer 1

49

Explanation:

We are given the polynomial:

`x^2+y^2+xy`

We want to evaluate when x=3 and y= -8. Therefore, we must substitute 3 for each x and -8 for each y.

`(3)^2+(-8)^2+(3*-8)`

Solve according to PEMDAS: Parentheses, Exponents, Multiplication, Division, Addition, Subtraction

Solve the parentheses first. Multiply 3 and -9.

3*-8=-24

`(3)^2+(-8)^2 + -24`

`(3)^2+(-8)^2-24`

Now, solve the exponents.

3^2= 3*3 =9

`9+ (-8)^2 -24`

-8^2= -8*-8= 64

`9+64-24`

Add 9 and 64

`73-24`

Subtract 24 from 73

`49`

The polynomial evaluated for x=3 and y= -8 is 49.

Answer 2

Answer: 49

Work Shown:

Replace x with 3, replace y with -8. Use order of operations PEMDAS to simplify.

x^2 + y^2 + x*y

3^2 + (-8)^2 + 3*(-8)

9 + 64 - 24

73 - 24

49