X − 4y = 7
5x + 9y = 6
5x − 20y = 35 //1st * 5
5x + 9y = 6
5x +9y - 5x + 20y = 6 - 35 //2nd - 1st
5x + 9y = 6
29y=-29
5x=6-9y
y=-1 //1st : 29
5x=6-9*(-1)
y=-1
x=15:5 //2nd : 5
y=-1
x=3
check:
for x=3 and y=-1 there is:
x − 4y = 7 is 3 − 4*(-1) = 7 is 7=7 ok
5x + 9y = 6 is 15-9=6 is 6=6 ok
answer: (3;-1) represents the solution.
Answer: Infinite solutions
Step-by-step explanation:
Answer: It should be -2
Step-by-step explanation:
Answer:
The amount of water need to be added is 5 liters.
Step-by-step explanation:
Let's "x" be amount of water in (liters) added to 15 liters of 40% of sugar syrup.
Now find the amount of sugar syrup = 40% of 15
= 0.4 × 15
The amount of sugar syrup = 6 Liters
To dilute 30% we need to find amount of water to be added.
So,
30% of (15 + x) = 6
0.3 × (15 + x) = 6
4.5 + 0.3x = 6
0.3x = 6 - 4.5
0.3x = 1.5
Dividing both sides, by 0.3, we get
x = 5
So, the amount of water need to be added is 5 liters.
Answer:
y = (2/3)x - 3
Step-by-step explanation:
Slope-intercept form: y = mx + b
Note that:
y = (x , y)
m = slope
x = (x , y)
b = y-intercept.
The point is given to you. Note that:
(x , y) = (0 , -3) ∴
x = 0
y = -3
The slope = m = 2/3
Plug in the corresponding numbers to the corresponding variable:
y = mx + b
-3 = (2/3)(0) + b
-3 = 0 + b
b = -3
Plug in -3 for b in the equation:
y = mx + b
y = (2/3)x -3
y = (2/3)x - 3 is your equation.
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