1. If the function fx=x2-2x-15 has roots at the points (-3, 0) and 5, 0, what is the vertex of the function? **

  (1, -16)

Step-by-step explanation:

The line of symmetry is halfway between the x-intercepts, at ...

  x = (-3 +5)/2 = 1

The line of symmetry goes through the vertex, so to find the y-coordinate of the vertex, we need to find f(1):

  f(1) = 1^2 -2(1) -15 = -16

The vertex of the function is (x, y) = (1, -16).

the largest number of the four options is 1.8 x 10-2

you have it in scientific notation.

1.80 x 10-6   = 0.00000180

1.80 x 10-4   = 0.000180 (bigger, or "less small", than the former one)

so

1.8 x 10-2       = 0.0180. as you see. the "less small", or the biggest one of them all.

as you have negative exponent, it means you are dividing 1.8 by 100 (i.e. moving the dot towards left, two times).

if you had positive exponent for the scientific notation, power of tenths, you would be multiplying times 100 (moving the dot towards right) as below:

1.8 x (10)2 = 180

so. if you have negative exponent in scientific notation, move the dot toward left. if it is positive, toward right as many times the exponent tells you.