helpppp i need explanation please!!

Question

We know that y-intercept of a function is the same as the value of the constant term. Stan knows this fact, so he states that the polynomial function f(x) = 4x^2 + 5x^2 + 8x does not have a y intercept. thenEXPLAIN how you would know he is wrong without actually looking at the graph. What is the y Intercept for this function.

 

Answer 1

A y intercept is a point on the graph where x is zero.

Generally, find the value of y intercept of any function by substituting x = 0.

In this case, the polynomial function is quadratic function.

If it has constant term in it's equation then it will be y intercept of the function.

For instance, y = x²  + 2x + 8

To find y intercept substitute x = 0 in y = x²  + 2x + 8

y = (0)²  + 2(0) + 8

y = 8

y intercept of above function is 8.

 

Now the polynomial function f(x) = 4x²  + 5x²  + 8x

Change f(x) to y.

y = 9x² + 8x

To find y intercept substitute x = 0 in y = 9x² + 8x.

y = 9(0)² + 8(0)

y = 0

y intercept of the polynomial function is 0.