100 points in correct answer deduction 40 in every wrong. 20 questions asnwered and the score 180 points how many wrong answer did he get?

Let the right = x

Let the wrong = y

100x - 40y = 180        (1)

x + y = 20                   (2)   Rearrange (2) to prepare for a substitution

x = 20 - y                    (3)  

100(20 - y) - 40y = 180    Put (3) into (1)  Remove the brackets.

2000 - 100y - 40y = 180  Collect like terms

2000 - 140y = 180            Subtract 2000 from both sides

-140y = 180 - 2000          

-140y = -1820                     Divide by - 140      

y = -1820/-140

y = 13

He had 13 incorrect answers

"image"

step-by-step explanation:

in most of these problems, the notation is that the point with a "prime" is the image of the point without. that is, b' is the image of b.

here, there is no dilation or reflection. there is simply translation (with no direction shown). which figure you call the "preimage" and which one you call the "image" is up to you. as a matter of convention, the naming is as described above.

idk

step-by-step explanation:

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