Without drawing the graph of the equation, determine how many points the given equation have in common with the x-axis and where
is the vertex in relation to the x-axis?
y = -2x^2 + x + 3
y = -2x^2 + x + 3
1 answer:
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.
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.
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Complete Question
The complete question is shown on the first uploaded image
Answer:
The solution is
Step-by-step explanation:
From the question we are told that
and
Generally the absolute value of the determinant of the Jacobian for this change of coordinates is mathematically evaluated as
So
=>
substituting for a, b, c,d
=>
=>
=>
Option C: is the coordinates of C after translation.
Explanation:
The triangle ABC has vertices at A(−3, 4), B(4, −2), C(8, 3).
Also, given that the triangle is translated 4 units down and 3 units left.
We need to determine the coordinates of the vertex C after translation.
The triangle is shifted 4 units down means subtracting 4 units from the y - coordinate of the graph.
Thus, it can be written as
Also, the triangle is shifted 3 units left means subtracting 3 units from the x - coordinate of the graph.
Thus, it can be written as
Thus, the translation is given by
The vertices of C after translation can be determined by
Thus, is the coordinates of C after translation.
Hence, Option C is the correct answer.