Mark for review (Will be highlighted on the review page) 1. Solve this equation: 80 = 3y + 2y + 4 + 1.

1 answer:

7 0

First combine the like terms 3y + 2y to get 5y. Then combine 4 + 1 to get 5. Your equation will now be 80 = 5y + 5. To solve for y, 5 needs to be subtracted from both sides of the equation leaving 75 = 5y. Final step to solving for y, 5 needs to be divided from each side of the equation leaving the final answer of
15 = y.

You might be interested in

What is -6x - 10(x - 4)

weeeeeb [17]

-16x+40 is the solution of this problem.

4 0

3 years ago

Evaluate f(2) for the function f(x) = 3x² + 2x - 5.

Softa [21]

Answer:

f(2)= 11

Step-by-step explanation:

you have to substitute 2 for every x you see:

f(x) = 3x² + 2x - 5

f(2)= 3(2)^2+2(2)-5

f(2)= 11

6 0

3 years ago

I just need help with three, four, and seven. Solve the system of linear equations, and determine if the equation has one soluti

likoan [24]

3. If $y=5x+9$ and $y=3x-2$ , then

$5x+9=3x-2\implies2x+9=-2\implies2x=-11\implies x=-\dfrac{11}2$

Then

$y=5\left(-\dfrac{11}2\right)+9=-\dfrac{55}2+9=-\dfrac{37}2$

(only one solution)

4. If $y+2=4x$ , then $y=4x-2$ . So we're told that $4x-5=4x-2$ but this is impossible, because that would that for any $x$ , we have -5 = -2. This is false, so this system has no solution.

7. "y is 6 less than 3 times x" means $y=3x-6$ . "x is 2 more than one-third of y" means $x=\dfrac13y+2$ . Solving the second equation for $y$ gives $y=3x-2$ , which would mean $3x-6=3x-2$ . But for the same reason as in (4), there is no solution. For any value of $x$ , this equation gives the false conclusion that -6 = -2.