Given: 8-2y – 3y -9=-11 Prove: y = 2

1 answer:

3 0

Step 1: group Y on left side
(-2 - 3)y = -5y

step 2: group constants on left side
8 - 9 = -1

step 3: form modified equation
-5y - 1 = 11

step 4: group constants
-5y - 1 + 1 = -11 + 1

step 5: cancel 1 on left side
-5y = -10

step 6: divide each side by -5
-5y/-5 = -10/-5

answer: y = 2

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Two lines that are skew can be parallel

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Answer: skew lines are two lines that do not intersect and are not parallel

Step-by-step explanation:

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3 years ago

A theater can seat 273 people. The number of rows is 8 less than the number of seats in each row. How many rows of seats are the

artcher [175]

R * s = 273
r = s - 8.....s = r + 8

r(r + 8) = 273
r^2 + 8r = 273
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r - 13 = 0
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r = 13
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Without drawing the graph of the equation, determine how many points the given equation have in common with the x-axis and where

Gala2k [10]

Remark
It's asking you to complete the square to find the vertex.

Solve
y = -2x^2 + x + 3 Put brackets around the first 2 terms.
y = (-2x^2 + x) + 3 Pull out the 2.
y = -2(x^2 - 1/2 x) + 3 Be especially observant of the sign on 1/2x Divide the middle term's number by 2 and square it.
y = -2(x^2 - 1/2 x + [(1/2) / 2]^2 ) + 3 [1/2 divided by 2 is 1/4. (1/4)^2 = 1/16; 2*(1/16) = 1/8
y = - 2(x^2 - 1/2 x + (1/4)^2 ) + 3 + 1/8
y = -2(x - 1/4)^2 + 3 1/8

Comment
Answer to your question. The maximum value (3 1/8) is above the y axis. That means the graph of the equation crosses the x axis twice. I'm going to include the graph because in answering the question, there is no harm in seeing the graph.