The measures of two of the sides of an equilateral triangle are 3x + 15 in. and 7x – 5 in. What is the measure of the third side in inches?
(1 point)
Responses
5
5
1
1
18
18
30
To find the measure of the third side, we can set up an equation with the two given sides. Since an equilateral triangle has all three sides equal in length, we can set the two given sides equal to each other:
3x + 15 = 7x - 5
To solve for x, we can subtract 3x from both sides:
15 = 4x - 5
Then, we add 5 to both sides:
20 = 4x
Finally, divide both sides by 4:
x = 5
Now that we have the value of x, we can substitute it back into either of the given sides to find the measure of the third side. Let's use the first given side, 3x + 15:
3(5) + 15 = 30
Therefore, the measure of the third side is 30 inches.
To find the measure of the third side of the equilateral triangle, we need to remember that in an equilateral triangle, all three sides are equal in length.
Let's set up an equation using the given measures of the two sides:
3x + 15 = 7x - 5
Now, we can solve for x:
3x - 7x = -5 - 15
-4x = -20
x = (-20)/(-4)
x = 5
Now that we have found the value of x, we can substitute it back into one of the original expressions to find the measure of the third side:
Third side = 3x + 15 = 3(5) + 15 = 15 + 15 = 30
Therefore, the measure of the third side is 30 inches.
To find the measure of the third side of the equilateral triangle, we need to set up an equation using the given measures of the two sides.
Since an equilateral triangle has all sides equal in length, we can set the two measures equal to each other:
3x + 15 = 7x – 5
To solve this equation for x, we can start by simplifying both sides. We can do this by combining like terms:
-5 + 15 = 7x - 3x
Simplifying further, we have:
10 = 4x
To isolate x, we divide both sides of the equation by 4:
10/4 = x
Simplifying the left side, we have:
2.5 = x
Now that we have the value of x, we can substitute it back into one of the given measures to find the length of the third side:
3x + 15 = 3(2.5) + 15 = 7.5 + 15 = 22.5
Therefore, the measure of the third side of the equilateral triangle is 22.5 inches.