bearing in mind that
standard form for a linear equation means
• all coefficients must be integers, no fractions
• only the constant on the right-hand-side
• all variables on the left-hand-side, sorted
• "x" must not have a negative coefficient
then we'd end up with 6x + y = 19.
The x coordinate of Q would be 5.
In order to find this, first note that P and R are exactly 2 away from each other (-1 to -3 is two away).
Now, we know that Q is 3 times as far away from R as P is given the ratio at the beginning. Therefore we know it is 6 away from R (2 * 3 = 6).
Now we simply add 6 to the R value to get the Q value.
-1 + 6 = 5
X + y = 51
x - y =15
2x = 66
x = 33
33 + y = 51
y = 18
Answer:
You have to look for the y-value for a given x-value.
f(-2) = 2
f(0) = 3
f(4) = -1
Rise over run
1/9
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