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If JKLM is a rectangle, JL = 2x+5 and MK =7x-40. Find x and MK

User HDT
by
4.2k points

2 Answers

3 votes

Answer:

x = 9

MK = 23

Explanation:

LL = MK (diagonals)

2x+5 = 7x-40

5x = 45

x = 9

MK = 7(9) -40

MK = 23

User Rahul Panzade
by
4.6k points
4 votes

Answer:

Explanation:

In a rectangle, diagonals are congruent

MK = JL

7x - 40 = 2x + 5 {Add 40 to both sides}

7x - 40 + 40 = 2x + 5 +40

7x = 2x + 45 {Subtract 2x form both sides}

7x - 2x = 2x - 2x + 45

5x = 45 {Divide both sides}

5x/5 = 45/5

x = 9

MK = 7x - 40

= 7*9 - 40

= 63 - 40

MK = 23

User Minyoung
by
3.8k points