So basically
D=RT
distance=rate times time
D=233
carlos speed=55
maria speed=50
total time=4.4 hours
so therefor we have to represent
carlos time
maria time
carlos distance
maria dstance
let's say that
remember that whatever carlost drove is 233 minus maria (time and distance)
and since we are solving for maria time and distnace, solve in terms of them
maria time=t
maria distance=d
carlos time=4.4-t
carlos distance=233-d
remember total D=RT
find their seperate equations
carlos
233-d=55(4.4-t)
maria
d=50(t)
use them to solve
233-d=55(4.4-t)
subsitute 50(t) for d
233-50t=55(4.4-t)
add 50t to both sides
233=55(4.4-t)+50t
distribute using distributiver protperty (a(b+c)=ab+ac)
55(4.4-t)=242-55t
233=242-55t+50t
add like terms
233=242-5t
add 5t to both sides
233+5t=242
subtract 233 from both sides
5t=9
divdie both sides by 5
t=1.8
maria drove 1.8 hours
the answer is A
Answer:
Step-by-step explanation:
y = ax² + bx + c
Plug the points into the equation to get a system of 3 equations with 3 unknowns a, b, and c.
-27 = 4a - 2b + c
-42 = 9a + 3b + c
-12 = a + b + c
(a,b,c) = (-4,1,-9)
y = -4x² + x - 9
Answer:
20.5 and 21.5
Step-by-step explanation:
It says 2 significant figures so the least it can possibly be is 0.5 less and the most it can be is 0.5 more as if it was, lets say 20.4 it would round down to 20 not 21.
The expression to evaluate is 32 + (8 - 2) * 4 - 6/3.
In the first step you can solve the parenthesis and the fraction => 32 + (6)*4 - 2.
In the second step you mutiply 6*4 => 32 + 24 - 2.
Finally, you do the maths: 32 + 24 - 2 = 54.
<span>Answer: 54</span>
