Lisa’s test grades are 79, 89, and 90. there will be one more test this year. if lisa wants her test average to be at least 88, what is the lowest grade she can get on her last test?

step-by-step explanation:

you can add the two numbers and divide the result by 2. or you can find the gap between the two numbers and add half of this to the smaller number.

(-5,-28)

i graphed to on desmos.