Which values of x and y would make the following expression represent a real number? (4 + 5i)(x + yi)

The value of x and y are all points which satisfies the equation , i.e.,(4,-5).

Explanation:

The given expression is,

Use distributive property to simplify the expression.

We know that

Combine likely terms,

In x+iy, x is the real part is iy is imaginary part. If the given expression represents a real number it means the imaginary part must be 0.

All the points which satisfies the above equation are the values of x and y for which the given expression is a real number.

Fom eg. (4,-5)

LHS=RHS, it means the point satisfies the equation and the value of x and y are (4,-5).

x=4 y=-5

Step-by-step explanation:

took the test and got a 100

( ͡° ͜ʖ ͡° ) copy and   paste it

step-by-step explanation:

second option

step-by-step explanation:

the measures of a triangle equal 180. use that to find x.

2x+3x+4x=180

9x=180

9x/9=180/9

x=20

now you know x, you know angle a is 40°, angle b is 60°, angle c is 80°.

because angle a is 40°, the first option doesn't work.

because angle b is 60°, the second option does work.

when you add angle a and b, you get 100°. complementary means it equals 90°, so the third option doesn't work.

when you add angle a and c, you get 120°, which is not 100.