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

step-by-step explanation:

step 1: solve one of the equations for one of the variables. let's solve the first equation for y:

step 2: substitute that equation into the other equation, and solve for x.

step 3: substitute x = 4 x = 4 x=4 into one of the original equations, and solve for y.