SAT Math 11.4 Geometry and Measurement. What is the y-intercept of a line parallel to y – 2x = 4 and passing through the point (1, 2)?
|Coordinate Geometry||Slopes, Parallel and Perpendicular Lines|
|Heart of Algebra||Solving linear equations|
|Parallel and Perpendicular Lines||Parallel Lines|
|Product Type||SAT Math|
|SAT Math||Geometry and Measurement|
So here’s our graph… and we want to figure out where a particular line is.
Well, we’re given the equation y – 2x = 4… but we need to get that thing into standard form.
y has to be all by its lonesome, here on the left… let’s add 2x to both sides.
y = 2x + 4. That's standard form.
If we plug in 0 for y… then x would work out to be -2. So let’s put a point at (-2,0).
If we plug in 0 for x… we get y equals 4. So… another point at (0,4).
And…here’s our line. Looks like for every one unit we move to the right,
we move up 2 units…
…so our slope is 2.
If we draw a parallel line that passes through (1,2)…
…then it will cross the y-intercept… at zero.
Eh, no. We were thinking maybe just a champagne toast…