21 - 16.75 is 4.25. Do the problem on a calculator and you'll get it.
What’s the cost before the tip? We need to know that before calculating the cost with the tip.
Answer: The two sides are 15m and 10m.
Step-by-step explanation:
Area = l x w
150 = l x w
There are two solutions for l
l 1= P/4+1/4√P2﹣16A
=50/4+1/4·√50^2﹣16·150=15m
l2 = P/4﹣1/4√P2﹣16A
=50/4﹣1/4·√50^2﹣16·150=10m