Find an expression Which represents the sum of(-10x-10y) and (-9x-7y) in Simplest terms

Solve this system of equations. 12x − 18y = 27 4x − 6y = 10

The length of a rectangle plus its width is 24 cm. the area is 143 square cm. what are the length and width of the rectangle?

Melissa is purchasing a $160,000 home and her bank is offering her a 30-year mortgage at a 4.9% interest rate. in order to lower her monthly payment, melissa will make a 20% down payment and will purchase 3 points. what will her monthly mortgage payment be? a. $645.98 b. $650.46 c. $662.93 d. $606.69