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5 votes
5 votes
Find ml if jk is 3x+11 and np is 45 and ml is 10x-12

trapezoid
it goes J to K
N to P
M to L
2 halvs
Kp is congruent to PL and Jn is congruent to NM

User Jamesdlin
by
3.4k points

1 Answer

23 votes
23 votes

Answer:


ML=58

Explanation:

Given


JK=3x+11,ML=10x-12,NP=45

See attachment

Required

Length ML

First, calculate x using the following equivalent ratios


JK:NP=NP:ML

Express as fraction


(JK)/(NP)=(NP)/(ML)

Cross Multiply


JK*ML=NP*NP

Substitute values:


(3x+11)*(10x-12)=45*45

Expand


30x^2-36x+110x-132=2025


30x^2+74x-132=2025

Collect like terms


30x^2+74x-132-2025=0


30x^2+74x-2157=0

Using a calculator:


x
-10 and
x
7

Given that:


ML=10x-12

Substitute values for x


ML=10*-10-12=-100-12=-112


ML=10*7-12=70-12=58

ML cannot be negative; So:


ML=58

User Avio
by
2.7k points