The sum of 1/7 of a number and 1/8 of that number gives 12

How many different triangles can be constructed with the angle measurements of 134° 10° and 36° ?

Estimate the area under the curve f(x) = 16 - x^2 from x = 0 to x = 3 by using three inscribed (under the curve) rectangles. answer to the nearest integer.

Two years ago a man was six times as old as his daughter. in 18 years he will be twice as old as his daughter. determine their present ages.