What is the fourth term in a(1)=−11 a(n)=a(n−1)⋅10

The equation x2 – 1x – 90 = 0 has solutions {a, b}. what is a + b?

In right ∆abc shown below, the midpoint of hypotenuse ac is located at d and segment bd is drawn.if ab = 12 and bc = 16, then explain why bd = 10. hint: consider what you know about the diagonals of a rectangle.

How is working backward similar to solving an equation?