Answer:
Two solutions (-4,-7) and (4,7)
Step-by-step explanation:
x = y + 3
x*y = 28
(y+3)*y=28
y^2+3y-28=0
(y+7)(y-4)=0
y=-7, y=4
x=-4, x=7
The answer is x and y have a weak, positive correlation.
Hi
7 = 14.70
15= X
so : X = 15*14.70 /7 = 31.5
15 liters of petrol cost 31.5
X+y=70
x=2y-5
x=larger number
y=smaller number
now plug in the value of x to only have one variable in the equation...
Way to solve for y:
(2y-5)+y=70
3y-5=70
add 5 on both sides...
3y=75
divide by 3 on both sides
y=25
1st way to solve for x:
now plug in y in the original equation...
x+25=70
subtract 25 on both sides...
x=45
2nd way to solve for x:
plug in y for the second equation...
x=25(2)-5
x=50-5
x=45
answer: the two numbers are 45 and 25.