4. 1,50
5. 0,50
6. Tawni swims the fastest because she swims at roughly 0,8 meters per second which is faster than the other two contestants.
Hello!
We can write this as the system of equations below. We have boxes A, B, and C.
A+B+C=9
B=A+1
C=B+1
First of all we can plug our B and C values into the first equation and solve for A.
A+A+1+A+1+1=9
3a+3=9
3a=6
a=2
Now we can plug our a value into the other equations.
B=2+1
B=3
C=3+1
C=4
Therefore, there are 2 rocks in one box, three in another, and 4 in the last.
I hope this helps!
B. Multiplying by 45 is the same as multiplying by 80%.
X = 0 ; y = 10 ; 10 = a(0) + b(0) + c
c = 10
x=2 ; y = 15 ; 15 = a(4) + b(2) + 10 ; 5 = 4a+2b
x=4 ; y=18 ; 18 = a(16) + b(4) + 10 ; 8 = 16a + 4b
2(5) = (4a+2b)2
-
<u> 8 = 16a + 4b
</u> 2 = -8a
a = -0.25
b = 2
y = (1/4)x^2 + 2x + 10 ; 4y = x^2 + 8x + 40
