-3x + y - 2z = 10 |* -1
3x - y +2z = -10
5x -2y -2z = 12
--------------------------- I add these equations term by term
8x - 3y = 2
-3x + y - 2z =10 ⇒ -3x + y - 2z =10
x -y +z = 23 | *2 2x - 2y + 2z = 46
----------------------------- I add these eq.
-x -y = 56
8x - 3y = 2
-x -y = 56
this is the system after i reduce it ( it has only two variables x and y)
Answer:
máy ...
xác suất để một máy tính bảng có hệ điều hành B sử dụng ổn định trong 2 năm đầu tiên. Add answer
First, you want to put all the numbers in order from least to greatest.
21, 33, 33, 42, 67, 79, 89
Now, you can use this song to help remember how to do these problems.
Cross off the sides till you get to the center. 1 is good, 2 is bad. (If you get two numbers in the middle) add then divide by two.
Cross off 21, then 89, then 33, then 79, then 33, then 67. Now, you're left with 42 in the middle. That is your median. Hope this helps! :)
Answer:
c is correct answer for you
Answer:
D. All three chose a valid first step toward solving the equation.
Step-by-step explanation:
Aaron, Blaine, and Cruz are solving the equation 4/7 (7 − n) = −1. Aaron started his solution by multiplying both sides of the equation by 7/4 . Blaine started by using the distributive property to multiply 4/7 by both 7 and −n. Cruz started by dividing both sides of the equation by 4/7 .
Which of the following is true?
A. Blaine and Cruz made an error in picking their first steps.
B. Cruz made an error in picking his first step.
C. All three made an error because the right side equals -1.
D. All three chose a valid first step toward solving the equation.
Given:
4/7(7 - n) = -1
Aaron:
4/7(7 - n) = -1
Multiple both sides by 7/4
4/7(7 - n) * 7/4 = -1 * 7/4
7 - n = -7/4
- n = -7/4 - 7
- n = (-7-28)/4
- n = -35/4
n = 35/4
Blaine:
4/7(7 - n) = -1
4/7(7 - n) × 7 = -1 × 7
4(7 - n) = -7
28 - 4n = -7
-4n = -7 - 28
- 4n = - 35
n = -35/-4
n = 35/4
Cruz:
4/7(7 - n) = -1
Divide both sides by 4/7
4/7(7 - n) ÷ 4/7 = -1 ÷ 4/7
4/7(7 - n) × 7/4 = -1 × 7/4
7 - n = -7/4
- n = (-7-28)/4
- n = -35/4
n = 35/4
D. All three chose a valid first step toward solving the equation.