3x - 7
The perimeter is the sum of all 3 sides of the triangle
To find the third side subtract the sum of the 2 known sides from the perimeter
x + 3 + 2x + 4 = 3x + 7
third side = 6x - (3x + 7 ) = 6x - 3x - 7 = 3x - 7
Ok this is not as hard as it seems
(4.5 feet)^2 times the number of students (13)
20.25 x 13
263.25 is the correct answer
I hope it helps :<
The answer is 10.2.
Since it's a percentage, you move the decimal two places to the left which gives you 0.12. Then, you multiply that by 85 and you get 10.2.
2X^2+22x+318=1270
2x^2+22x-952=0
x^2+11x-476=0
(x+28)(x-17)=0
x=17