Law of sine and cosine

Find the measure of angle Z
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Find thethe measure of angle C

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Solvetriangle ABC if a = 15, c = 18, and the measure of angle C= 68°.??

Can someone help me with this three problem please thanks i appriciate it :)

The law of sines states:

sin(α) / A = sin(β) / B = sin(γ) / C

Where A is the length of the side opposite angle α, etc.

For the first problem:

sin(X) / x = sin(Z) / z

Solve for Z:

sin(Z) = zsin(X) / x
Z = arcsin(zsin(X) / x)
Z = arcsin[(10)sin(96°) / 48]
Z ≈ 11.96°

For the second problem:

sin(C) / c = sin(B) / b
sin(C) = csin(B) / b
C = arcsin(csin(B) / b)
C = arcsin[(17)sin(47°) / 13]
C ≈ 73.02°

For the third problem:

sin(A) / a = sin(C) / c
sin(A) = asin(C) / c
A = arcsin(asin(C) / c)
A = arcsin[(15)sin(68°) / 18)]
A ≈ 50.59°

You can find angle B by summing all the angles:

50.59° + B + 68° = 180°
B ≈ 61.41°

And finally, find side b using the law of sines again:

sin(B) / b = sin(C) / c
b = csin(B) / sin(C)
b = (18)sin(61.41°) / sin(68°)
b ≈ 17.05