Consider the table of values.
$x$x | $9$9 | $18$18 | $27$27 | $36$36 |
---|---|---|---|---|
$y$y | $-68$−68 | $-131$−131 | $-194$−194 | $-257$−257 |
Is $y$y increasing or decreasing?
increasing
decreasing
For every $1$1 unit increase in the $x$x value, by how much does $y$y change?
Use your answer to the previous part to state the algebraic rule linking $x$x and $y$y.
Give your answer as an equation.
Find the equation of the line through $\left(2,7\right)$(2,7) that is parallel to the $y$y-axis.
Find the equation of the line through $\left(3,5\right)$(3,5) that is parallel to the $x$x-axis.
Write down the equation of a line whose gradient is $2$2 and crosses the $y$y-axis at $\left(0,1\right)$(0,1).
Express your answer in gradient-intercept form.