Step-by-step explanation:
Part 1: How to calculate the width
1-
[tex]a ^{2} + b ^{2} = c ^{2} [/tex]
This is pythagoras theorem. the slanted side is C so fill it in with 89 and the right side can either be a or b; let's say b. now fill this in.
2-
[tex]a ^{2} + 39 ^{2} = 89 ^{2} [/tex]
Now work out the squares (squaring means multiplying a number by itself)
2-
[tex] {a}^{2} + 1521 = 7921[/tex]
3- a2=7921-1521 work out the subtraction (a2 means a squared)
4- a2= 6400 Now take the root of that because you want to know a not a squared.
5-
[tex] \sqrt{6400} = 80[/tex]
A equals 80
Part 2: calculating area
1- the formula for the area of a triangle is area= 1/2 × length x width
2- 1/2 × 39 x 80= 3120 cm2 ( cm squared)
