Algebra Jeopardy Round 2

Lines

100

What is the y-intercept of y=2x-4

The point (0,-4)

200

Define the slope of a line.

The slope is: the change in y/the change in x rise/run

300

Please provide an equation of a line parallel to y=-3x+4

Ex. y=-3x+-2

400

Given 2x+3y=8, what are the x and y intercepts?

x-intercept: (4,0) y-intercept: (0, 8/3)

500

Please provide an equation for the line passing through the points (-1,-1) and (2,5).

y+1=2(x+1) y-5=2(x-2)

Miscellaneous

100

Given a circle of radius 4, what are the circle's diameter and circumference?

d=8 c=8π

200

Please define a perpendicular bisector.

A perpendicular bisector passes through the midpoint of a segment at a 90 degree angle.

300

Please give the distance formula.

d = sqr.rt. [ (x-x1)^2 + (y-y1)^2 ]

400

What are zeros? (how do they appear on a graph? what is true about x and y when zeros occur?)

Zeros are x-intercepts, or the points where a graph crosses the x axis. When zeros occur, y=0.

500

Mr. Beck gives Ms. Danforth $30 to go buy candy for his students. If Ms. Danforth buys 7 candy bars for $1 and 4 candy bars for $2, how much money will she have left?

$20

Factoring

100

What does FOIL stand for?

First Outside Inside Last

200

Please factor: 4x^2 - 8x

4x(x-2)

300

Factor x^2 - 8x + 16

(x-4)^2

400

Distribute completely to get a trinomial: (1/2)(2x+2)(x-4)

x^2 - 3x - 4

500

Factor: 6x^2 - 5x - 6

(3x+2)(2x-3)

Quadratics and Completing the Square

100

What are the x-intercepts of the equation y=(x-3)(x+2)

The points (3,0) and (-2,0).

200

Which equation represents a parabola, and why: 1) y = 2x^2 - x + 3 2) y - 1 = 4x

Equation 1 is a parabola, because it has an x^2 term.

300

Fill in the blanks: x - ___x + 4 = (x - __ )^2

x-4x+4=(x-2)^2

400

Which of the following equations could represent the trajectory of a rocket (on Earth, under normal conditions)? Why? Line 1: y = 2x^2 + 4 Line 2: y = x^2 - 6x - 1 Line 3: y = -3x^2 + x +2

Line 3 could represent the path of a rocket because the x^2 has a negative coefficient, forming an negative or upside-down parabola.

500

Solve by completing the square: x^2 - 4x - 12 = 0.

x=-2,6

Solving Equations

100

Simplify: x = (1/2) x 24 x sqrt.[49]

x = 84

200

Solve for x. 2x-3=-x+9

x=4

300

Four pioneers and one missionary come to a river, where they find several cannibals. There are twice as many cannibals as the difference between pioneers and missionaries. How many cannibals are there?

There are 6 cannibals (uh oh!!!)

400

Find the intersection between the lines y = -4x + 3 and y = x + 8

The point (-1,7)

500

Given the following equation for the path of a ball, where distances are measured in feet, find the ball's maximum height. y=-2x(x-4)

4 feet.