What is the area of a triangle 7.8cm height and 12.8 cm with

Mathematics

1 answer:

elena55 [62]3 years ago

4 0

First: Multiply the measurements.
• 7.8 x 12.8 = 99.84
Second: Divide by 2.
• 99.84/2 = 49.92

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What is the value of c in the equation y = 4x^2 -10x + c if the y-coordinate of the vertex is -7

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Answer: $c=-\frac{3}{4}$

Step-by-step explanation:

Find the x-coordinate of the vertex with this formula:

$x=\frac{-b}{2a}$

In this case:

$a=4\\b=-10$

Substituting values, we get:

$x=\frac{-(-10)}{2(4)}=\frac{5}{4}$

Now we can substitute the coordinates of the vertex into the equation $y = 4x^2 -10x + c$ and then solve for "c".

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Lyrx [107]

Answer:

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