1. Solving Quadratic Equations
ALGEBRA 1 LESSON 9-1
Solve each equation by graphing the related function.
a. 2x2 = 0
b. 2x2 + 2 = 0
c. 2x2 – 2 = 0
Graph y = 2x2
Graph y = 2x2 + 2
Graph y = 2x2 – 2
There is one solution, x = 0.
There is no solution.
There are two solutions, x = ±1.
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2. Solving Quadratic Equations
ALGEBRA 1 LESSON 9-1
A museum is planning an exhibit that will contain a large globe. The surface area of the globe will be 315 ft2. Find the radius of the sphere producing this surface area. Use the equation S = 4 r2, where S is the surface area and r is the radius.
5.007 r
The radius of the sphere is about 5 ft.
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3. Solving Quadratic Equations
ALGEBRA 1 LESSON 9-1
1. Solve each equation by graphing the related function. If the equation has no solution, write no solution.
a. 2x2 – 8 = 0
b. x2 + 2 = –2
2. Solve each equation by graphing the related function.
a. m2 – 25 = 0
b. 49q2 = 9
3. Find the speed of a 4-kg bowling ball with a kinetic energy of 160 joules. Use the equation E = ms2, where m is the object’s mass in kg, E is its kinetic energy, and s is the speed in meters per second. ±2
no solution ±5 3 7 1 2
about 8.94 m/s
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