Question

Please help im having trouble with this one

Answer 1

Answer:

∠T=22°

Step-by-step explanation:

Given triangle RST with sides 5 cm, 7 cm, 3 cm.

If all sides are given and find the missing angle, we use cosine rule

$CosA=\frac{b^{2}+c^{2} -a^{2}}{2bc}$

Where,

sides are a, b, c and angle A, B, & C are opposite angles respectively.

So,

$CosT=\frac{r^{2}+s^{2} -t^{2}}{2rs}$

$cosT=\frac{25+49-9}{70}$

$cosT=\frac{65}{70} =\frac{13}{14}$

T = 21.79°≈ 22°

That's the final answer.

Answer 2

Answer:

22 degrees to the nearest degree.

Step-by-step explanation:

Use the Cosine Rule

3^2 = 5^2 + 7^2 - 2*5*7*cos T

9 = 74 - 70 cos T

cos T = (74-9)/ 70

cos T = 65/70

m < T = 21.8 degrees.