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:
1) In this question we've been given "a", the leading coefficient. and two roots:
2) There's a theorem, called the Irrational Theorem Root that states:
If one root is in this form then its conjugate . is also a root of this polynomial.
Therefore
3) So, applying this Theorem we can rewrite the equation, by factoring. Remembering that x is the root. Since the question wants it in this expanded form then:
Answer:
f(x) > 0 over the interval
Step-by-step explanation:
If f(x) is a continuous function, and that all the critical points of behavior change are described by the given information, then we can say that the function crossed the x axis to reach a minimum value of -12 at the point x=-2.5, then as x increases it ascends to a maximum value of -3 for x = 0 (which is also its y-axis crossing) and therefore probably a local maximum.
Then the function was above the x axis (larger than zero) from , until it crossed the x axis (becoming then negative) at the point x = -4. So the function was positive (larger than zero) in such interval.
There is no such type of unique assertion regarding the positive or negative value of the function when one extends the interval from to -3, since between the values -4 and -3 the function adopts negative values.
Let number of hours needed to work = x
Multiply number of hours by rate: 15x
Add what you already have saved:
15x + 215
This needs to equal at least 800:
The equation becomes:
15x + 215 >= 800
Solve for x:
15x + 215 >= 800
Subtract 215 from both sides
15x >= 585
Divide both sides by 15
X >= 39
They have to work at least 39 hours.
Answer:
x > 1/5
Step-by-step explanation:
All of these three triangle inequalities must be satisfied:
AB +BC > AC
BC +CA > BA
CA +AB > CB
___
Taking these one at a time, we have ...
AB +BC > AC
3x +4 + 2x +5 > 4x
x +9 > 0 . . . . . subtract 4x
x > -9
__
BC +CA > BA
2x +5 + 4x > 3x +4
3x > -1 . . . . . . subtract 3x+5
x > -1/3 . . . . . divide by 3
__
CA + AB > CB
4x + 3x +4 > 2x +5
5x > 1 . . . . . . subtract 2x+4
x > 1/5
___
The only values of x that satisfy all of these inequalities are those such that ...
x > 1/5