What is x in 2(x+20)=90

Select the lengths in centimeters that would form a right triangle

The midpoints of the sides of the large square are joined to form a smaller square. what is the area of the smaller square

Sketch the region enclosed by the given curves. decide whether to integrate with respect to x or y. draw a typical approximating rectangle and label its height and width. y= 5x, y=7x^2then find the area s of the region.