Question

Help i don't understand this at all

Answer 1

(a) C = 1.41

(b) D = 3.46

Explanation:

(a)

(Im pretty sure your teacher already thought this so im skipping most of the steps, but feel free to ask in the comments)

Find C (Cosine version)

Use Formula for Cosine/Sine (You can use both of these formula because both of the angles are 45°)

Cos =
`(adj)/(hyp)`

`Sin = (Opp)/(Hyp)`

Put the 45° with the Cos/Sin and substitute the adj and hyp with the correct values. I'll be substituting the adj with c for simplicity.

Cos45° =
`(c)/(2)`

Multiply both sides by 2 so that c can be alone

2 ⋅ Cos45° =
`(c)/(2)` ⋅ 2

= 2Cos45° = c

Flip it so that the c goes in first for it to be easier to understand

c = 2Cos45°

Put the 2Cos45° into a scientific calculator and we're done

c = 1.41

Find C (Sine Version)

Same thing with Cosine Version

Sin45° =
`(c)/(2)`

2 ⋅ Sin45° =
`(c)/(2)` ⋅ 2

c = 2Sin45°

c = 1.41

(b)

Find D

Use Formula for Sine

Sin =
`(Opp)/(Hyp)`

Put the 60° with the Sin and substitute opp and hyp with correct values. Substitute Opp with d.

Sin60° =
`(d)/(4)`

Multiply both sides by 4 so d can be alone

4 ⋅ Sin60° =
`(d)/(4)` ⋅ 4

d = 4Sin60°

d = 3.46