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Can someone please help me with math.

Can someone please help me with math.-example-1
User Axelrotter
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1 Answer

2 votes

Answer:

1 is b

2 is c

3 is b

Explanation:

Initial co-ordinate of p = ( 2, -2)

Rule for rotation 180° about the origin

(x,y) ----> ( -x , -y )

Meaning of the rule: To find the coordinates of a point that was rotated 180° about the origin all we have to do is add negative signs in front of the x and y values of the coordinates. THE NUMBER STAYS THE SAME. THE ONLY THING THAT CHANGES IS THE SIGN

* add - to the coordinates *

- ( 2 , -2 )

-1 * 2 = -2

-1 * -2 = 2

we end up with ( -2, 2 )

Hence the answer is B

For this one a rectangle was dilated and we have to find the scale factor and the new width.

We are given the pre image width (3) and length (4) and the new image length (12)

We can find the scale factor by dividing the new image length by the pre image length ( Note that you have to use corresponding sides. Like pre image height over new image height or pre image length over new image length. etc. )

So scale factor = 12 / 4 or 3

Now to find the new image width

We can do this by multiplying the pre image width (3) by the scale factor (3)

So new image width = 3 * 3

3 * 3 = 9

Hence the width of the enlarged print is C 9 inches

For this one we need to find x using angle rules

The angles shown are supplementary angles meaning that the sum of the two angles is 180

That being said we can create an equation to solve for x

180 = 64 + 4x + 16

Now we just solve using basic algebra

step 1 combine like terms

64 + 16 = 80

now we have 180 = 4x + 80

step 2 subtract 80 from each side

80 - 80 cancels out

180 - 80 = 100

now we have 100 = 4x

step 3 divide each side by 4

100/4 = 25

4x/4=x

we're left with x = 25

User Vinze
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