Answer:
use -9 to multiply the first equation
use -4 to multiply the second equation.
Step-by-step explanation:
5x-4y=28.....eqn (1)×-9
3x-9y=30....eqn(2)×-4
-45x+36y=-252
-(-12x+36y=-120)
therefore, -33x÷33 =-132÷-33
x=4.
substitute (x=4) in any of the equation. I'm just going to use eqn 1.
5x-4y=28
5(4)-4y=28
20-4y=28
-4y =28-20
-4y÷-4 = 8÷-4
y=-2
so, x=4, y=-2
Note: for proof of answers substitute the answers for x and y and see if you have the same result...e.g
5(4)-4(-2)=28.
Answer:
I believe the answer is 12.57
Step-by-step explanation:
The answer is the first one.
Explanation:
X^3 stays the same because there are no other cubed numbers in the problem
Next you combine the x^2s
The x^2s are +3x^2 and +2x^2
Since they are both positive, you add them: 3x^2 + 2x^2 = 5x^2
Next you do the x values
-x and +6x, also known as 6x - x = 5x
Lastly, you just add in the -2 and get:
X^3 + 5x^2 + 5x - 2
Multiply 3 by 2 and you get six I think
