Answer:
Step-by-step explanation:
Let the speed of the car is x, then the speed of motorcycle is x + 20
The distance = 120 km
<u>Time:</u>
- 120/x = 120/(x + 20) + 1
- 120(x + 20) = 120x + x(x +20)
- 120x + 2400 = 120x + x² + 20x
- x² + 20x = 2400
- x² + 2*10x + 10² = 2500
- (x + 10)² = 50²
- x + 10 = 50
- x = 40
Speed of the car is 40 km/h
Speed of the motorcycle is 60 km/h
Answer:
First, plot the y-intercept. The y-intercept is 1, so plot the point (0,1).
Then go up 2 points and to the right 3 points and plot a point there. (3,3)
We go to the right because the slope is positive.
Draw a line through the two points.
Step-by-step explanation:
y = mx+b
m = slope
b = y-intercept
Answer:
see explanation
Step-by-step explanation:
x² + 3x + 7 = 5 ( subtract 5 from both sides )
x² + 3x + 2 = 0 ← in standard form
(x + 2)(x + 1) = 0 ← in factored form
Equate each factor to zero and solve for x ( zero product rule )
x + 2 = 0 → x = - 2
x + 1 = 0 ⇒ x = - 1
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x² - 2 = - 2x² + 5x ( subtract - 2x² + 5x from both sides )
3x² - 5x - 2 = 0 ← in standard form
(3x + 1)(x - 2) = 0 ← in factored form
Equate each factor to zero and solve for x
3x + 1 = 0 ⇒ 3x = - 1 ⇒ x = - 
x - 2 = 0 ⇒ x = 2
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(x + 3)² + 4x = 0 ← expand left side using FOIL and simplify
x² + 6x + 9 + 4x = 0
x² + 10x + 9 = 0 ← in standard form
(x + 9)(x + 1) = 0 ← in factored form
Equate each factor to zero and solve for x
x + 9 = 0 ⇒ x = - 9
x + 1 = 0 ⇒ x = - 1
One way to approach this problem is to go ahead and find the actual equation in slope-intercept form.
The slope of the line thru (3,6) and (5,4) is m = (6-4) / (3-5), or -2/2, or -1.
Subbing the known values of m, x and y, we get:
4 = -(5) + b. Then b = 9.
The correct equation (representing the data values in the table) is y = -x + 9.
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