Question

Find the value of x in these right-angled triangle, correct two decimal places A=20 B=7

Answer 1

There are two possibilities: 1) A is the hypotenuse:
`C \approx 18.74`, 2) A is not the hypotenuse:
`C \approx 21.19`

Explanation:

Let be C the remaining side of the triangle. Given that triangle is right-angled and the remaining side can be found by Pythagorean Theorem, there are two options by using the two known sides:

1) A is the hypotenuse

`20^(2) = 7^(2) + C^(2)`

`C^(2) = 20^(2)-7^(2)`

`C = \sqrt{20^(2)-7^(2)}`

`C \approx 18.74`

2) A is not the hypotenuse

`C^(2) = 20^(2) + 7^(2)`

`C = \sqrt{20^(2)+7^(2)}`

`C \approx 21.19`