13 x 85 = 1105
78 + 91 = 169
169 / 1105 = 6.5
Answer:
x = 4 , y = -1
Step-by-step explanation:
x - 3y = 7 -- (1)
3x - 3y = 15 -- (2)
Rewriting (1), x = 3y + 7 -- (1)'
Substituting (1)' into (2),
3 ( 3y + 7 ) - 3y = 15
9y + 21 - 3y = 15
6y = -6
y = -1 -- (3)
Substituting (3) into (1),
x - 3 ( - 1 ) = 7
x + 3 = 7
x = 4 -- (4)
According to (3) and (4),
x = 4 , y = -1
Answer:
x=-1
Step-by-step explanation:
-15=22x+7
Subtact 7 both sides
-15-7=22x+7-7
-22x=-22
Divide both sides by -22
-22x=-22
x=-1
Answer:

Step-by-step explanation:
When a quantity "A" varies DIRECTLY with another quantity "B", we can write the proportionality equation as:
A = kB
Where k is the proportionality constant (to be found)
In this problem, it is given x varies DIRECTLY with y, so we can write:
x = ky
Also, given, x = 11, y = -3, so we plug these into the equation and first find k:
x = ky
11 = k(-3)
k = -11/3
Now, we need to find x when y = 8, so we substitute and find x:
