Substitute y=4x to the second equation:
x^2 + (4x)^2 = 17
x^2 + 16x^2 = 17
17x^2 = 17
x^2 = 17/17
x^2 = 1
x = 1 and -1
When x=1, y=4(1) = 4
When x=-1, y=4(-1) = -4
Thus the solutions would be (1,4) and (-1,-4). That would correspond to D. and A.
Answer:
I am only in like 5th grade, but I'll do my best to answer this.
Step-by-step explanation:
Volume of a cylinder: πr^2h where "r" is the radius and "h" is the height
π * 4^2 because since the width is 8, half of that is the radius
π * 4^2 * 8 because you still have to multiply that by the height to find the full space inside
= π * 4^2 * 8
V ≈ 402.12 (rounded to two decimals)
Answer: B. 41 3/5 ounces of icing per cake
Step-by-step explanation:
- 52/5 divided by 1/4. Keep 52/5, change the division sign into a multiplication sign, and flip 1/4 to 4.
- The new equation should be 52/5 * 4. The answer to this is 208/5, which simplified is 41 3/5.
T=time
d=st
r=train speed
p=plane speed
<span>160=rt
</span><span>720=pt
speed of plan is 20kmph less than 5 times speed of train
p=5r-20
we notice that 160 times 4.5=720
times first equaton by 4.5
720=4.5rt
720=pt
set equal
4.5rt=pt
divide both sides by t
4.5r=p
sub </span><span>p=5r-20 for p
4.5r=5r-20
minus 4.5r from both sides
0=0.5r-20
add 20 to both sides
20=0.5r
times 2 both sides
40=r
sub back</span><span>
p=5r-20
p=5(40)-20
p=200-20
p=180
plane is 180kmph
train is 40kmph
</span>
The absolute value of a number is how far away it is from 0 on a number line.
Example) 2 is two numbers away from 0, but neg. 2 (-2) is also two numbers away from 0
So basically. A positive number has the absolute value of itself. (2= a value of 2) and negative numbers have the absolute value of the positive form of that number. (-9= a value of 9)
Numbers that have the absolute value of 2: 2 and -2
Numbers that have the absolute value of 4: 4 and -4
Numbers that have the absolute value of 9: 9 and -9
You are looking to add your numbers together to make a positive.
So the answer is the positive answers to the absolute values: 2,4,9
2+4+9=15
15 is a positive number.