if UVW ~ RST ,what is the value of x?
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X=15
30/42=X/21
Cross multiply.
42x=630
Divide.
630/42= 15
x=15
I know its kind of confusing, it took me a while to get geometry down too.
But I hope this helps :)
Answer:
x = 15
Step-by-step explanation:
Since the triangles are similar, we can say that the ratio between the respective sides of the first triangle and the 2nd is constant.
Basically, VW / ST = VU/SR = WU/TR = k, where k is a positive real number
Solving for k is simple:
k = VU/SR = 42/21 = 2
So we found out that the 1st triangle is the 2nd triangle but scaled up 2 times.
We use this to find x.
ST * 2 = VW
2x = 30
x = 15