# How to do question 4. a and b?

Feb 3, 2018

$y = 2.25 x$
$d = 24622 m$

#### Explanation:

$y = m x + b$
$b = 0$, because it goes through the origin.
$m = \frac{{y}_{1} - {y}_{2}}{{x}_{1} - {x}_{2}} ,$ which is true for any two points which are included by the function. In this case we have the points:
${p}_{1} \left(0 | 0\right)$
${p}_{2} \left(10 | 22.5\right)$
$m = \frac{22.5 - 0}{10 - 0} = 2.25$
$y = 2.25 x + 0 = 2.25 x$

For the distance we use pythagoras:

${a}^{2} + {b}^{2} = {c}^{2}$
$a = 10 , b = 22.5 , c = u n k n o w n$
${10}^{2} + {22.5}^{2} = {c}^{2}$
$606.25 = {c}^{2}$
Than, we take the root.
$\sqrt{606.25} = c \approx 24.622 k m \left(24622 m\right)$