the quadratic function f(x)=ax2+bx+5 is given. Determine a and b so that the graph of the function is symmetrical about the ordinate axis and passes through the point T(2,7)
Question
Answer:
If the graph should be symmetrical then
x=2,y=7 and x=-2 y=7
if x=2 y=7
$$ \left(2\right)^2a+\left(2\right)b+5=7 $$
$$ \left(4\right)a+\left(2\right)b=2 $$
if x=-2 y=7
$$ \left(4\right)a+\left(-2\right)b=2 $$
Solve for a an b
$$ a=\frac{1}{2},b=0 $$
Answer:
$$ f\left(x\right)=\frac{1}{2}x^2+5 $$
solved
general
11 months ago
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