The length of one of the equal legs of an isosceles triangle is 8 cm less than 4 times the length of the base. If the perimeter is 29 cm, find the length of one of the equal legs.
2006-06-23 13:44:56 · 9 answers · asked by Anonymous in Science & Mathematics ➔ Mathematics
bY THE WAY, TO THE ONE WHO SAYS I AM CHEATING, YOU CAN JUST KISS MY BUT! i AM SLOW WITH MATH AND HAVE GIVEN A PRACTICE EXAMPLE IN THE HOPE THAT I CAN UNDERSTNAD HOW THE ANSWER WAS ACHIEVED.
2006-06-23 13:50:45 · update #1
Here's the process you would use to solve the problem.
First, you need to know that an isosceles triangle has two equal sides.
Therefore, you have two variables in the problem
x = length of leg (there are two of these)
y = length of base
We know that "the length of one of the equal lengths of an isosceles triangle is 8 cm les than 4 times the length of the base." Therefore, we can write "x" in terms of "y":
x = 4y - 8
Furthermore, we know that the perimeter is 29 cm. Now we can set up an algebraic expression to solve for "x."
2x + y = 29 (initial equation)
2(4y-8) + y = 29 (substitution)
y = 5 (solved)
We have the length of the base ("y"). Now we can solve for the length of one of the equal legs. Remember from above that
x = 4y - 8
x = 4(5) - 8
x = 12
Solved!
If you are still confused, draw an isosceles triangle to visualize the problem. Label the base "y" and the two legs "x."
2006-06-23 13:58:36 · answer #1 · answered by student2000 2 · 0⤊ 0⤋
X = length of base
4X - 8 is the length of each side
(X) + (4X-8) + (4X-8) = Perimeter = 29cm
X + 4X -8 + 4X - 8 = 29
X + 4X + 4X -8 -8 = 29
9X -16 = 29
9X = 45
X = 45/9 = 5cm for X = length of the Base
substitute in 5cm for X in each equation above.. for sides:
4X - 8 = sides
4(5)-8 = 20 - 8 = 12 cm for each of the sides
2006-06-23 20:53:08 · answer #2 · answered by ♥Tom♥ 6 · 0⤊ 0⤋
4B-8=1 equal leg
so
4B-8+4B-8+B=29
B IS THE BASE
Now combine like terms
4B+4B+B=9B
-8-8=-16
So 9B-16=29
9B=29+16
9B=45
B=45 divided by 9
B=5
4 times the base of 5 is 20 minus 8 = 12
Answer 12
Check Work 12+12+5=29
2006-06-23 21:01:16 · answer #3 · answered by cmartin0203 2 · 0⤊ 0⤋
legs=12 base=5
2006-06-23 20:50:34 · answer #4 · answered by word 3 · 0⤊ 0⤋
x = length of base
2 (4x -8) + x = 29
8x -16 + x = 29
9x = 45
x = 5
base is 5
sides are 12 (from 4x - 8)
2006-06-23 20:48:15 · answer #5 · answered by csucdartgirl 7 · 0⤊ 0⤋
12cm per leg
2006-06-23 20:47:47 · answer #6 · answered by Neilman 5 · 0⤊ 0⤋
why dont you do your own homework you wierdo
2006-06-23 22:46:09 · answer #7 · answered by monkyodoom 2 · 0⤊ 0⤋
cant help you on that
2006-06-23 20:47:06 · answer #8 · answered by proffesor 4 · 0⤊ 0⤋
please, do your own homework. this is cheating.
2006-06-23 20:49:01 · answer #9 · answered by michumunky 2 · 0⤊ 0⤋