26x3=78
78-x=72
x=6
She needs to buy at least 6 more to have enough for 26 students
a^2+a-ab+3ab^2-b^2 I hope this helps
Answer:
w = 13yd, l = 18yd
Step-by-step explanation:
let x be width, so x+5 = length
Perimeter is sum of all 4 sides, and since opposite sides equal in rectangle,
P = 2(l+w)
= 2(x+5 +x)
= 4x + 10
Since perimeter is give as 62yd, equation is
4x + 10 = 62
4x = 52
x = 13
The solution for that proplem is X=4,1
Use the Pythagorean theorem
<span>the hypotenuse is the ladder which is 20 ft and the base is 12 ft thus </span>
<span>a^2 + b^2 = c^2 </span>
<span>a^2 + 144 = 400 </span>
<span>a^2 = 256 </span>
<span>a = 16 </span>
<span>so its 16 ft</span><span />