Answer:
Use by Prime factorisation method
Answer:

Step-by-step explanation:
We are given with two equations
first equation is 
second equation is

we find the result of subtracting two equation
subtract the second equation from the first, so
first equation - second equation, multiply second equation by -1 and then add it with first equation


Now add both equations, we get

Answer:
(3,15) and (-1.5, 1.5)
Step-by-step explanation:
If g(x) = 2x² - 3
X varies directly as y
x = ky
3 = 2k
k =

when x =9
9 =

y

= y
∴y = 6
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Answer:
The equation has a maximum value with a y-coordinate of -21.
Step-by-step explanation:
Given

Required
The true statement about the extreme value
First, write out the leading coefficient

means that the function would be a downward parabola;
Downward parabola always have their vertex on top of the parabola and as such, the function has a maximum value.
The maximum value is:

Where:

So, we have:



Substitute
in 


<em>Hence, the maximum is -21.</em>