What is the *x*-intercept of a line passing through the points (-1, 1.5) and (0, 4)?

**Maps to Category 1 of the book.**

**Answer posted on 08/22/2021: Answer is -1.6 or -4/2.5.**

Since *x* = 0 at *y*-intercept, the given point (0, 4) is the *y*-intercept of the line.

Determine the slope, and plug the slope and the *y*-intercept in the *y = mx + b* equation.

Slope = (4 - 1.5)/(0-(-1)) = 2.5/1 = 2.5.

Hence, the equation is *y = *2.5*x + *4.

Since *y* = 0 at *x*-intercept, set *y* = 0 in the above equation and solve for *x*.

0* = *2.5*x + *4 --> 2.5*x = *-4 --> x = -4/2.5 = -1.6.

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