Answer: This parabola has 0.3875 x-intercepts,
<span>representing the times when the dolphin's height above water is </span>
0 feet.
The x-intercept is the point where the graph crosses the x-axis, which is when the value is y=0.
The calculation for y=0 would be
<span>Y = -16x2 + 32x - 10
</span><span>0 = -16x2 + 32x - 10
</span>-8x2 + 16x - 5=0
-b +-√(b^2-4ac) /2a=
-16 +-√(16^2-4(-8)(-5)) /2(-8) =
-16+- √(256-160/ -16 =
-16+- √(96/ -16 =
-16+- 9.8/ -16 =
x1= 0.3875
x2= -1.6125
This really is left up to you as long as you have an odd number in the tens place and a 7 in the ones place. How big (or small) the number is is up to you. As long as it is at least 17, it's pretty much up to you.
X(a+b)-y(a+b)
*factor out (a+b)*
=(a+b)(x-y)