D. The elevator takes 37.5 seconds to move down to the lobby.
8x+y=300
y= 300-8x
y= 300 - 8 (37.5)
y = 300-300
y = 0
wheb y =0 that means that the height is 0
Answer: 1/6
Step-by-step explanation:
A die has 6 numbers which are 1, 2, 3, 4, 5 and 6.
Odd numbers in a die = 1, 3 and 6
Numbers greater than 4 = 5 and 6
Probability of rolling an odd number = 3/6 = 1/2
Probability of rolling a number greater than 4 = 2/6 = 1/3
We then multiply both values gotten. This will be:
= 1/2 × 1/3
= 1/6
Therefore, the probability of rolling an odd number the first time and a number greater than 4 the second time is 1/6.
We can use linear combinations of the equations to eliminate variables.
3x - 4y = 1
-2x + 3y = 1
To eliminate y we'll make the linear combination of 3 times the first equation minus four times the second.
9x - 12y = 3
-8x + 12y = 4
Adding,
x = 7
We could solve for y directly but let's use another linear combination, twice the first plus three times the second:
2(3x - 4y) + 3(-2x + 3y)= 2(1)+3(1)
y = 5
Check: 3(7)-4(5)=1 good. -2(7)+3(5)=1 good.
Q18 Answer: (7,5)
y = -3x + 5
5x - 4y = -3
4y +1(5x - 4y) = 4(-3x + 5) + 1(-3)
5x = -12x + 20 -3
17 x = 17
x = 1
y = -3(1) + 5 = 2
Check: 5(1) - 4(2) = -3 good
Q19 Answer (1,2)
6x + 5y = 25
x = 2y + 24
6x = 12y + 144
5y = 25 - 12y - 144
17y = -119
y = -119/17= -7
x = 2y+24= 10
Check: 6(10)+5(-7)=25 good 2y+24=2(-7)+24=10=x good
Q20 Answer (10,-7)
3x + y = 18
-7x + 3y = -10
9x + 3y = 54
9x - -7x = 54 - -10
16x = 64
x=4
y = 18 -3x = 18-12=6
Check: 3(4)+6=18 good, -7(4)+3(6)=-10 good
Q21 Answer: (4,6)
Answer:
The inequality for amount x (in dollars) is given by
x ≤ $33 - (cost of necklace).
Step-by-step explanation:
Let the cost of the necklace be $ y.
The amount for the necklace is constant and it is less than $33 and it is also known that the amount for the necklace will be spent.
Therefore after the necklace has been purchased and the amount deducted from $33 the remaining amount can be used completely or partly to purchase the other item.
Let the cost in dollars of the other item be $x.
The inequality for amount x (in dollars) is given by
x ≤ $33 - (cost of necklace)
3/7 or 3:7 because you tossed the dice 7 times and got an even number 3 of those times.
