Hmmm I think 16 - 10 = 10 ( - 8 - 6 ) = 6
I believe you are expected to simplify. To do this all you do is group like terms (x, x², x³ etc.) and then simplify the coefficients.
13. 10z + 7z - 19z² - 5z² - 17z
first you can rearrange and group like terms (remember the bring the sign in front of each term with it). I would do it like this:
-19z² - 5z² +10z + 7z - 17z
Now simplify the coefficients:
-24z² + 0z
you can omit the 0z and your simplified answer is
-24z²
Main thing to remember here is that z and z² cannot be simplified together, nor can any variable that has an exponent because the exponent makes them differ.
Answer: D
Step-by-step explanation:
Answer:
x = 1/4
y = -1/2
z = 9/4
Step-by-step explanation:
Here we have a system of 3 equations with 3 variables:
4*x + 2*y + 1 = 1
2*x - y = 1
x + 3*y + z = 1
The first step to solve this, is to isolate one of the variables in one of the equations, let's isolate "y" in the second equation:
2*x - y = 1
2*x - 1 = y
Now that we have an expression equivalent to "y", we can replace this in the other two equations:
4*x + 2*(2*x - 1) + 1 = 1
x + 3*(2*x - 1) + z = 1
Now let's simplify these two equations:
8*x - 1 = 1
7*x - 3 + z = 1
Now, in the first equation we have only the variable x, so we can solve that equation to find the value of x:
8*x - 1 = 1
8*x = 1 + 1 = 2
x = 2/8 = 1/4
Now that we know the value of x, we can replace this in the other equation to find the value of z.
7*(1/4) -3 + z = 1
7/4 - 3 + z = 1
z = 1 + 3 - 7/4
z = 4 - 7/4
z = 16/4 - 7/4 = 9/4
z = 9/4
Now we can use the equation y = 2*x - 1 and the value of x to find the value of y:
y = 2*(1/4) - 1
y = 2/4 - 1
y = 1/2 - 1
y = -1/2
Then the solution is:
x = 1/4
y = -1/2
z = 9/4
9/10 or 0.9
Hope this helps