Let m and j be the current ages of Matthew and Jenny, respectively.
Now, Matthew is 3 times as old as Jenny, so the variables are in the following relation:
In 7 years, both of them will be 7 years older, i.e. their ages will be m+7 and j+7, and Matthew will be twice as old:
Now, remembering that m=3j, we can rewrite the second equation as
So, Jenny is 7 and Matthew is 21 (he's 3 times older).
In fact, in 7 years, they will be 14 and 28, and Matthew will be twice as old.
Assume if it is cloudy, then you are outside.
Answer:
V: 700
Step-by-step explanation:
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Answer:
y=1/∛4 divides the area in half
Step-by-step explanation:
since the minimum value of x² is 0 (for x=0 ) and for y=1
1 = 25*x² → x= ±√(1/25) = ±1/5
then the total area between y=1 and y = 25*x² is bounded to x=±1/5 and y=0 . Since there is a direct relationship between x and y , we can find the value of x=a that divides the region in 2 of the same area. thus
Area below x=C = Area above x=C
Area below x=C = Total area - Area below x=C
2*Area below x=C = Total area
Area below x=C = Total area /2
∫ 25*x² dx from x=c to x=-c = 1/2 ∫ 25*x² dx from x=1/5 to x=-1/5
25*[c³/3 - (-c)³/3] = 25/2 * [(1/5)³/3 - (-1/5)³/3]
2*c³/3 = (1/5)³/3
c = 1/(5*∛2)
thus
y=25* x² = 25*[1/(5*∛2)]² = 1/∛4
thus the line y=1/∛4 divides the area in half
y =x+10
y =6x+30
substitute x+10 into the 2nd equation anywhere you see y
x+10 = 6x+30
subtract x from each side
x-x+10 = 6x-x+30
10 = 5x+30
subtract 30 from each side
10-30=5x+30-30
-20 = 5x
divide by 5 on each side
-20/5 =5x/5
-4=x
now solve for y
y=x+10
y = -4 +10
y=6
Answer: x=-4
y=6
or (-4,6)
3. y = -3x-6
6x+5y=-30
6x+5(-3x-6) =-30
5x-15x-30=-30
-20x-30=-30
-20x=0
x=0
y = -3x-6
y=-6
