You can start by subtracting different equations from each other.
3x + 2y + 3z = 1
subtract
3x + 2y + z = 7
2z = -6
divide by 2
z = -3
add the following two expressions together:
3x + 2y + z = 7
3x + 2y + 3z =1
6x + 4y + 4z = 8
subtract the following two expressions:
6x + 4y + 4z = 8
5x + 5y + 4z = 3
x - y = 5
^multiply the whole equation above by 3
3x - 3y = 15
subtract the following two expressions:
3x - 3y = 15
3x + 2y = 10
-5y = 5
divide each side by -5
y=-1
take the following expression from earlier:
x - y = 5
substitute y value into above equation
x - - 1 = 5
2 negatives make a positive
x + 1 = 5
subtract 1 from each side
x = 4
Therefore x = 4, y = -1, z = -3
I checked these with all 3 equations and they worked :)
(it's quite complicated, comment if you don't understand anything) :)
First put the words in an algebraic format or a model. D = 3.5(√H). Now determine what the question is asking. It's height. Plug in the value of D. Distance is 35 km.
35 = 3.5(√H) We want to get H by itself. First thing to get away from it is 3.5. So divide 35 by 3.5 And 3.5(√h) by 3.5.
10 = √H To get rid of √ do the opposite raise to the power of 2
10² = (√H)²
100 = H
You must be 100 kilometers above ground to see 35 kilometers
Put it in the calculator and the answer is 3.4305
X >- 5
-2x -4 < 3x +21
+4 +4
-2x < 3x +25
-3x -3x
-5x < +25
-5x/-5 25/-5
X > -5
Answer:
C. 47
Step-by-step explanation:
5(8 + 7)
Expand the brackets. Brackets mean to multiply.
5(8 + 7)
5 * 8 + 7
= 40 + 7
= 47