How do I find X for this triangle?

1 ⤊

How do I find X for this triangle?

The triangle has sides x-1, x, and 5. The perimeter is 12 units.

2007-11-15 12:39:32 · 4 answers · asked by Jenny 1 in Science & Mathematics ➔ Mathematics

4 answers

Add up the sides to get the perimeter:
(x - 1) + x + 5 = 12

Now add together like terms:
x - 1 + x + 5 = 12
2x + 4 = 12

Subtract 4 from both sides:
2x = 8

Divide both sides by 2:
x = 4

(Therefore the sides are 3, 4 and 5).

2007-11-15 12:44:23 · answer #1 · answered by Puzzling 7 · 1⤊ 0⤋

x-1+x+5=12
2x+4=12
2x=8
x=4

2007-11-15 12:56:00 · answer #2 · answered by anonymous 3 · 0⤊ 0⤋

x-1 + x =12-5
x-1+x=7
2x=8
x=4

2007-11-15 12:44:56 · answer #3 · answered by Sleeping Troll 5 · 0⤊ 0⤋

Just saying... I'd point to the x. =) lol just kidding. Im not sure....

2007-11-15 12:48:41 · answer #4 · answered by Natasha:) 2 · 0⤊ 0⤋