If you have to write the equation then it would be "5k + 6.7"
Y - x - 3 = 0
y = x + 3
y = x^2 - x - 12
x + 3 = x^2 - x - 12
x^2 - x - 12 - x - 3 = 0
x^2 - 2x - 15 = 0
(x - 5)(x + 3) = 0
x - 5 = 0 y = x + 3
x = 5 y = 5 + 3
y = 8
x + 3 = 0 y = x + 3
x = -3 y = -3 + 3
y = 0
so ur solutions are : (5,8) and (-3,0)
20 inches is 400
10 inches is 200
5 iches is 100
So 20+10+5=35
Which means 400+200+100= 700
So the frequency of a 35 inch string is 700 cycles per second
To multiply fraction do top x top and bottom x bottom
so convert

into

then do