2. Complex Numbers & Quadratics

Solve the following equations simultaneously.

Equation $1$1 | $y=x^2+3x$y=x2+3x |

Equation $2$2 | $y=-x+21$y=−x+21 |

a

First solve for $x$`x`.

b

Find the value of $y$`y` at the point of intersection where $x=3$`x`=3.

c

Find the value of $y$`y` at the point of intersection where $x=-7$`x`=−7.

Easy

Approx 4 minutes

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Explain why the x-coordinates of the points where the graphs of the equations y = f(x) and y = g(x) intersect are the solutions of the equation f(x) =g(x); find the solutions approximately. ^Combine polynomial, rational, radical, absolute value, and exponential functions