Determine The missing number in the equation

3 + 9= +4

Abbey purchased a house using a fixed rate mortgage. the annual interest rate is 4.2% compounded monthly for 20 years. the mortgage amount is $235,000. what is the monthly payment on the mortgage? this isn't a multiple choice question have to show my work

What number should be added to the expression x^2+3x+ in order to create a perfect square trinomial? 3/2 3 9/4 9

The base of a triangle exceeds the height by 9 inches. if the area is 180 square inches, find the length of the base and the height of the triangle.