1. A.
x parrot fish + y triggerfish = 320 total fish.
y = 7x shows that there are 7 times as many triggerfish.
2. C
x + y shows a total score of 425.
y = 2x - 70 shows that Michael's score, y, is 70 less (minus) than twice Kathryn's
3. write two equations
x + y = 27 total feet
2x + 3 = y
Substitute 2x + 3 for y in the first equation
x + (2x + 3) = 27
3x + 3 = 27
3x = 24
x = 8
Substitute 8 in to either equation to find the other length.
8 + y = 27
y = 19
The shorter piece is 8 and the longer piece is 19
4. x + y = 3200 people -> y = 3200-x
8x + 12y = 33,040 dollars
8x + 12(3200 - x) = 33040
8x + 38400 - 12x = 33040
-4x = -5360
x = 1340 (1340 children)
1340 + y = 3200
y = 1860 adults
5. I don't think the numbers for this were put in correctly because I get a decimal and a negative number when I solve for it but hopefully if you do get the correct cost/amount of coins you will understand this well enough to do it on your own. Hope I helped!
Answer:
Length: 23.38
Width: 3.34
Step-by-step explanation:
First I drew out a diagram so that I could visibly see the problem. [ a rectangle with 7x on one side and x on the other.
So to find the area you multiply length time width and 7x times x is 7x^2. The actual area is given: 78, so you set that equal to 7x^2.
Then you want to divide by 7 to get 11.14. Then you want to take the square root of 11.14 to get 3.338 which rounds to 3.34 {try not to round until the very end]. This gives you the width of the rectangle, so to find the length you would have to multiply x by 7 to get 23.38. When you multiply the length and width (3.34 x 23.38) you get 78.08 which can round to 78.
7x^2 = 78
x^2 = 78/7
x^2= 11.142...
x = sqrt(1.142...)
x = 3.338 --> 3.34 --> width
3.34 x 7 --> 23.38 --> length
3.34 x 23.38 --> 70.8
Answer:
.............
Step-by-step explanation: