Could you help me number 10 on page 70 please? I kept getting 0 as the answer

Yep! Here’s the question:

I think the easiest way to go here is to use the calculator to graph. Don’t worry about the ≥ signs, just graph the lines and remember that the ≥ means anything on or above the lines you see.

Now, remember that you’re looking for the lowest possible y-coordinate that’s on or above both of those lines. In other words, you’re looking for the y-coordinate of the intersection! Since you’ve already graphed the lines on your calculator, it’s probably easiest just to use the calculator to find the intersection: (–1.33, 2.33).

2.33 is the answer you’d grid in (or its fraction form: \dfrac{7}{3}).

Solving algebraically is also not too cumbersome. Since both equations are in y = form already, substitute and solve for x:

    \begin{align*}-4x-3&=\dfrac{1}{2}x+3\\\\-6&=\dfrac{9}{2}x\\\\\-\dfrac{4}{3}&=x\end{align*}

Once you have x, plug it into either equation to get y:

    \begin{align*}y&=-4\left(-\dfrac{4}{3}\right)-3\\\\y&=\dfrac{16}{3}-\dfrac{9}{3}\\\\y&=\dfrac{7}{3}\end{align*}

 

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