SOLUTION: The perimeter of a triangle is 13 inches. Side b is twice the length of side a, and side c is 1 inch more than side a. What are the lengths of all three sides?

Algebra ->  Triangles -> SOLUTION: The perimeter of a triangle is 13 inches. Side b is twice the length of side a, and side c is 1 inch more than side a. What are the lengths of all three sides?      Log On


   

Question 954432: The perimeter of a triangle is 13 inches. Side b is twice the length of side a, and side c is 1 inch more than side a. What are the lengths of all three sides?
Found 2 solutions by macston, MathLover1:
Answer by macston(5194) About Me  (Show Source):
You can put this solution on YOUR website!
a, b, and c are sides of a triangle;P=perimeter=a+b+c=13 in
b=2a
c=a+1in
a+b+c=13in Substitute for b and c.
a+2a+a+1in=13n
4a+1in=13in Subtract 1 in from each side.
4a=12in Divide each side by 4.
a=3in ANSWER 1: Side a is 3 inches.
b=2a=2(3in)=6in ANSWER 2: Side b is 6 inches.
c=a+1in=3+1in=4inANSWER 3: Side c is 4 inches
CHECK:
P=a+b+c
13in=3in+6in+4in
13in=13in

Answer by MathLover1(20850) About Me  (Show Source):
You can put this solution on YOUR website!

The perimeter of a triangle is:P=a%2Bb%2Bc
given:
P=13in
side a
side b=2a
side c=a%2B1in
substitute given values in P=a%2Bb%2Bc
13in=a%2B2a%2B%28a%2B1in%29..............solve for a
13in=4a%2B1in
13in-1in=4a
12in=4a
12in%2F4=a
highlight%28a=3in%29
now find other two sides:

side b=2a=>highlight%28b=6in%29
side c=a%2B1in=> highlight%28c=4in%29