The question states the 3rd side is 10cm less than the 2nd side. The keyword is less, less means subtract. Knowing we have to subtract we can eliminate the 3rd and 4th answer. Since the 2nd is equal to “s”, and the third side is 10cm less than the 2nd, the 3rd side must be equal to:
20.9 ft This is a right triangle trigonometry question because N is 90 degrees. MN is adjacent to M and LM is the hypotenuse. Adjacent any hypotenuse use the cosine function. plug in known values switch cos(20) and x using the products property plug into calculator to get 20.9 ft
A(w)=50w-w2 if the perimeter is 100, I plugged in possible values for the width...I used w=15 and length = 35 for a perimeter of 100. then I plugged these values in the possible equations until I found the correct one giving me an area of 525 (15x35) . I could not think of an easier way.