What's the value of X in the figure

145 (degrees) X (2x + 15)

There are 15 plates and each plate is either 7 or 12 inches diameter. which systems of equations do you use to find the number of 7 inch plates, x and 12 inch plates, y

Solve the system of equations using the linear combination method. {4x−3y=127x−3y=3 enter your answers in the boxes.

Solve this 364x-64x=300x and 12(x2–x–1)+13(x2–x–1)=25(x2–x–1)