Answer:

Step-by-step explanation:
Cost of 4 TVs = $ 680
<u>Finding</u><u> </u><u>the</u><u> </u><u>cost</u><u> </u><u>of</u><u> </u><u>1</u><u> </u><u>TV</u>

<u>Finding</u><u> </u><u>the </u><u>cost</u><u> </u><u>of</u><u> </u><u>7</u><u> </u><u>TVs</u>
Since, the cost of 7 TVs is more than that of 1 TV. So, the cost of 1 TV is multiplied by 7

Hope I helped!
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Answer:
4x + y = 15 or y = -4x + 15
Step-by-step explanation:
7 = 2[-4] + b
-8
15 = b

If you want it in <em>Standard </em><em>Form</em>:
y = -4x + 15
+4x +4x
___________
4x + y = 15 >> Line in <em>Standard Form</em>
I am joyous to assist you anytime.