So somebody plz explain how to !

for the following system, use the second equation to make a substitution for y in the first equation.

3x + y = 1
y + 4 = 5x

what is the resulting equation?

a.) 3x + 5x - 4 = 1
b.) 3x + 4 - 5x = 1
c.) 3x + 5x + 4 = 1

Me ! write an equation for the interior angles of this triangle that uses the triangle sum theorem

What is the value of x in the equation 6(x + 1) – 5x = 8 + 2(x – 1)?

Phyllis and chen are saving money to go to a football game. each friend starts with some money and saves a specific amount each week. phyllis made a graph to show the total she has saved at the end of each week. chen wrote an equation to show the total, y, he has saved at the end of each week, x. y = 15x + 15 compare the amount that each friend has when both friends start saving. select the correct answer from the drop-down menu to complete the statement. phyllis starts with $ and chen starts with $