Gradient= -3/2 Equation: Y=mx+c Y=2 , X=8
So you substitute the numbers in
2=(-3/2) x 2 + c (then you backtrack to solve for c which is the y intercept)
2=-3+c
5=c So the equation should be Y=-3/2x+5
You follow the rules for the quadratic formula, where
x= (-b +- √(b²-4ac) )/2a
Filling a, b and c in yields
x = (8 +- √(64-164) ) / 2 =>
x = (8 - √-100)/2 or x = (4 + √-100)/2
Well, √-100 = 10i, so then you simplify to the last answer, D:
x = 4-5i or x=4+5i
It’s 3!! I checked on a calculator :)
<h3>Given</h3>
... f(x) = x² -4x +1
<h3>Find</h3>
... a) f(-8)
... b) f(x+9)
... c) f(-x)
<h3>Solution</h3>
In each case, put the function argument where x is, then simplify.
a) f(-8) = (-8)² -4(-8) +1 = 64 +32 + 1 = 97
b) f(x+9) = (x+9)² -4(x+9) +1
... = x² +18x +81 -4x -36 +1
... f(x+9) = x² +14x +46
c) f(-x) = (-x)² -4(-x) +1
... f(-x) = x² +4x +1
