Question

Given: ΔABC; a= 10; b = 13, and ∠C = 70°. Find the length of side c to the nearest whole number

Answer 1

`c=13\ units`

Explanation:

we know that

Applying the law of cosines

`c^2=a^2+b^2-2(a)(b)cos(C)`

we have

`a=10\ units\\b=13\ units\\C=70\°`

substitute

`c^2=10^2+13^2-2(10)(13)cos(70\°)`

`c^2=180.07`

`c=13\ units`