Solve by graphing of the related function, and finding its zeros X²-7x-30

Answer 1

Hi, I'd recommend graphing y=x²-7x-30 on Desmos and you'll find the zeroes of this function are the values of the x-coordinates where y=0. We can factor x²-7x-30 as (x-10)(x+3), and as y=(x-10)(x+3), we can set y equal to zero to find the zeroes of this function.

From here, we see that y=(x-10)(x+3)=0.

So we have two equations, namely that x-10 = 0 and x+3 = 0.

x-10 = 0 gives us that x=10

x+3 = 0 gives us that x=-3.

So our zeroes are x=10, x=-3.