Question

Shortanswer question

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Answer 1

Two lines will be parallel if they have the same gradient. Lines in the form\[y=mx+b\]are gradient-intercept form.

If you rearrange your equations into that form, you can compare the gradients. To make the other line parallel, choose 'a' that will give you a gradient equal to the other.

Answer 2

how do we re arrange? so is 5 from (5x) the gradient for the first one and a from (ax) the gradient of the other?

Answer 3

\[5x-y+10=0 \rightarrow y=5x+10\]after adding 10 to both sides.

Answer 4

The first line has gradient 5.

Answer 5

\[ax+4y-3=0 \rightarrow 4y=3-ax \rightarrow y = \frac{3-ax}{4}=-\frac{a}{4}x+\frac{3}{4}\]

Answer 6

You need a such that\[-\frac{a}{4}=5\]

Answer 7

So a is -20.

Answer 8

how did that become -a/4 x + 3/4 ?

Answer 9

\[y=\frac{3-ax}{4}=\frac{3}{4}-\frac{ax}{4}=-\frac{ax}{4}+\frac{3}{4}=-\frac{a}{4}x+\frac{3}{4}\]

Answer 10

oh okay makes sense :))) I'm just not so good at re arranging.

Answer 11

practice practice practice

so you don't get ruined in tests for nothing

Answer 12

Very true :D