In parallelograms, opposite sides are congruent, meaning that they are the same lengths. So, we have:
y - 4x = 9
-x + 4 = y
Add x to both sides of the second equation:
y + x = 4
y - 4x = 9
This is a system of linear equations. Solve by eliminating the y and subtracting the two equations:
5x = -5
x = -1
Use x to solve for y:
y + (-1) = 4
y = 5
So, x = -1 and y = 5.
Answer:
Regular price of a ticket = $60
Step-by-step explanation:
Given:
On purchasing museum tickets in advance customers get 10% off on the regular price of ticket.
Anias paid the sale price of ticket = $54
To find the regular price of ticket.
Solution:
Let the regular price of ticket in dollars be
Discount offered for booking in advance = 10%
Discount amount in dollars = 
Sale price of a ticket in dollars= Regular price - Discount amount= 
Sale price given for a ticket = $54
So, we have:

Dividing both sides by 0.9

∴ 
∴ Regular price of a ticket = $60
180 I believe because all angles in a triangles will ALWAYS add up to 180
The predicted value of y when x =7 is -8.5
<h3>How to predict the y value?</h3>
Start by drawing the line of best fit through the points
See attachment for the graph.
From the attached graph, we have the following value
y = -8.5 when x = 7
Hence, the predicted value of y when x =7 is -8.5
Read more about scatter plots at:
brainly.com/question/2749543
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