Answer:
y=1
Step-by-step explanation:
2y+5y-7=0
Combine y: 7y-7=0
Move 7 over: 7y=7
Divide by 7:y=1
Remark
What this is trying to tell you is that you have two factors. Each in turn can be zero, but they cannot be zero at the same time. You will get that kind of question, just not now.
So either - n = 0 or 5n - 4 =0
Solution
- n = 0 Multiply both sides by - 1
(-1)*(-n) = 0*-1
n = 0
5n - 4 = 0 Add 4 to both sides.
5n = 4 Divide by 5
n = 4/5
Comment
B and D are both wrong 4/5 is positive. and those list n as -4/5 which is wrong.
A is wrong because the function will not go to 0 if n = -1
Answer
C <<<<Answer
Answer:
13 hours
Step-by-step explanation:
Average speed = Distance traveled / time taken
⇒ Distance = Average speed × Time
d = s × t
For the first trip;
Average speed = 280 mph
d₁ = 280t₁ ------(1)
where;
d₁ is the distance covered to get to the destination
t₁ is the time taken to get to the destination
For the second trip;
Average speed = 240 mph
d₂= 240t₂ ------(2)
where;
d₂ is the distance covered on the way back
t₂ is the time taken on the way back
The trip is the same distance to and fro. Therefore,
d₁ = d₂
Substituting the equation for d₁ and d₂
280t₁ = 240t₂ ------(3)
It took one hour less time to get there than it did to get back, then,
t₁ = t₂ - 1
t₂ = t₁ + 1 ------(4)
Substituting equation (4) into equation (3)
280t₁ = 240(t₁ + 1)
280t₁ = 240t₁ + 240
280t₁ - 240t₁ = 240
40t₁ = 240
t₁ = 240/40
t₁ = 6 hours
From equation (4)
t₂ = t₁ + 1
t₂ = 6 + 1
t₂ = 7 hours
The total time for the trip is t₁ + t₂ = 6 + 7
= 13 hours
Answer:
Shows how to quickly check if a matrix product is defined and, if it is, how to ... You can use this fact to check quickly whether a given multiplication is defined.
Step-by-step explanation:
Let, the integers = x,(x+1)
x*(x+1) = 56
x²+x = 56
x²+x-56 = 0
x²+8x-7x-56=0
x(x+8)-7(x+8)=0
x+8= 0 OR x-7=0
x = -8 OR x = 7
it would be -8 & -7 or 7 & 8
