# Thread: Perimeter, Probability, and solving an expression

1. ## Perimeter, Probability, and solving an expression

1. One side of a triangle is 4 cm longer than the shortest side and 2 cm shorter than the longest side. The perimeter is 38 cm. Find the dimensions of the triangle.

2. A spinner with eight equal sections numbered 1 through 8 is spun 50 times. The number 3 is recorded 8 times. Determine the experimental probability of spinning an 8.

3. Solve bx – cx = 7 for x.

Please..help. I would really appreciate it, i need it in soon. Reviewing for my exams.

2. Originally Posted by Power
1. One side of a triangle is 4 cm longer than the shortest side and 2 cm shorter than the longest side. The perimeter is 38 cm. Find the dimensions of the triangle.
Side 1: $\displaystyle x$
Side 2: $\displaystyle x - 4$
Side 3: $\displaystyle x + 2$

$\displaystyle (x) + (x - 4) + (x + 2) = 38$

$\displaystyle 3x - 2 = 38$

$\displaystyle 3x = 40$

$\displaystyle x = 13,333$

Originally Posted by Power
3. Solve bx – cx = 7 for x.
$\displaystyle x(b - c) = 7$

$\displaystyle x = \frac{7}{b - c}$

Originally Posted by Power
Please..help. I would really appreciate it, i need it in soon. Reviewing for my exams.
I know next to nothing about probability, but I'll read through that question again and see if I can make anything out

3. Thanks man, your reply helped me a lot in problem no. 2, I never thought of factoring out the x variable.

But in problem 1, I still dont understand how can the sides equal the way you have them, can you please explain a little bit more.

4. Originally Posted by Power
Thanks man, your reply helped me a lot in problem no. 2, I never thought of factoring out the x variable.

But in problem 1, I still dont understand how can the sides equal the way you have them, can you please explain a little bit more.
Remember in a triangle the perimeter = side 1 + side 2 + side 3

Also one side has a value of $\displaystyle x$ (We don't know what it is)

But it's 4 cm longer than another side, so the latter must be $\displaystyle x - 4$

Because it's 2 cm shorter than a third side, the third side must be $\displaystyle x + 2$