Answer:
a. =11+ 1
b. =4x+ (-7y) + (-5z) +6
c. (-3x) + (-8y) +(-4)+(-8/7z)
Step-by-step explanation:
a. 20 - 9 + 8 -7
=11+ 1 ( this is obtained by solving)
b. 4x - 7y - 5z + 6
=4x+ (-7y) + (-5z) +6
We multiply the negative sign with the positive sign to get a minus so the answer remains the same and the expression is written as an addition sum.
c. -3x - 8y - 4 - 8/7z
-[ 3x+8y+4+8/7z]
or
(-3x) + (-8y) +(-4) +(-8/7z)
The minus sign is taken as common leaving the expression with the plus only.
It can be written in the same manner as above, adding the negative terms so that the expression is written as a sum.
I think the answer to this question is 18
X + y = 15
Rearrange this to isolate for x.
x = 15 - y
x + z = 20
Rearrange this to isolate for x also.
x = 20 - z
Since they are both equal to x, that means they are equal to each other (x = x)
Set them equal to each other.
15 - y = 20 - z
Now, isolate for y.
y = 15 - 20 + z
Now, use y + z = 25 and isolate for y.
y = 25 - z
Since they are both equal to y, we set them equal to each other.
15 - 20 + z = 25 - z
Solve for z
z + z = 25 - 15 + 20
2z = 30
2z/2 = 30/z
z = 15
Now you can plug the value for z into the other equations to find y and x.
x + z = 20
x +15 = 20
x = 20-15
x = 5
y + z = 25
y + 15 = 25
y = 25 - 15
y = 10
Answer:
Cross Multiplying.
Step-by-step explanation:
By multiplying each ratio by the second number of the other ratio, you can determine if they are equivalent. Multiply both numbers in the first ratio by the second number of the second ratio. For example, if the ratios are 3:5 and 9:15, multiply 3 by 15 and 5 by 15 to get 45:75.
