Read the vertical-axis intercept and gradient from an equation

What is the gradient?

Move the gradient slider through negative, zero and positive values. Watch the line's direction and where it crosses each axis

Which statement is true across all the settings?

Read the coefficient and the constant

Make the vertical variable the subject before reading the gradient and intercept. Either order of terms is valid

1. 1Gradient Keep the sign of the horizontal-variable coefficient. It gives the vertical change for one unit to the right \(\displaystyle y=11-4x\quad\Rightarrow\quad m=-4\)
2. 2Vertical-axis intercept Set the horizontal coordinate to zero. The constant is the vertical coordinate, and the crossing is a point \(\displaystyle \begin{aligned}x&=0\\y&=c\\P&=(0,c)\end{aligned}\)
3. 3Missing terms No constant means a zero intercept. No horizontal-variable term means a zero gradient \(\displaystyle \begin{aligned}y&=-6x+0\\y&=0x+9\end{aligned}\)
4. 4Divide every term First remove the horizontal-variable term from the left. Then divide every term by the vertical-variable coefficient \(\displaystyle \begin{aligned}5y+7x&=30\\5y&=30-7x\\y&=6-\frac{7}{5}x\end{aligned}\)

Find the vertical-axis intercept value

Set the horizontal coordinate to zero

Find the gradient

Make the vertical variable the subject before reading its gradient

Which is the first incorrect line?