Answer:
a>0
Step-by-step explanation:
if a is negative then the subtraction sign would switch. therefore, for the expression to have a negartive value a must be greater than 0
For the case of a line through
(
2
,
7
)
and
(
1
,
−
4
)
we have
slope
m
=
Δ
y
Δ
x
=
−
4
−
7
1
−
2
=
−
11
−
1
=
11
Using the point
(
2
,
7
)
we can write the equation of the line in point slope form as:
y
−
7
=
m
(
x
−
2
)
where the slope
m
=
11
.
That is:
y
−
7
=
11
(
x
−
2
)
To get point intercept form, first expand the right hand side so...
y
−
7
=
11
x
−
(
11
⋅
2
)
=
11
x
−
22
Then add
7
to both sides to get:
y
=
11
x
−
15
=
11
x
+
(
−
15
)
This is point intercept (
y
=
m
x
+
c
) form with slope
m
=
11
and intercept
c
=
−
15
.
Set up
Let the dimes = d
Let the pennies = p
Let the quarters = q
Equations
You cannot mean that the pennies and dimes have equal numbers. That would mean that each had 21.5 members. Now could you mean that the dime and penny amount could be the same with 43 coins that total 4.00. Four dollars means that you need 40 dimes alone. It must mean that you are including quarters.
p + d + p = 43 (1)
p = d (2)
p +10d +25q = 451 (3)
Note how this last equation = was derived. You have to multiply the dimes by 10 and he quarters by 100 and the total by 100 to get the numbers all in pennies.
Put the results of 2 into 1.
2p + q = 43 (4)
You need to modify equation 3 as well.
p + 10p + 25q = 451
11p + 25q = 451 (5)
Solve the new equations
2p + q = 43 (4)
11p + 25q = 451 (5)
Multiply 4 by 25
25(2p- + q = 43)
50p + 25q = 1075 (6) Subtract (5) from (6)
<u>11p + 25q = 451
</u>39p = 624 Divide by 39
p = 624 / 39
p = 16
Since the pennies and dimes are equal there are 16 dimes
p + d + q = 43
16 + 16 + q = 43
32 + q = 43
q = 11
Check
16 + 10*16 + 11*25 = ?
16 + 160 + 275 = ?
451 = ?
Nice problem. Thanks for posting.
Let X is the random number Erik thinks of, and Y is the random number Nita thinks of.
Both X and Y are in the range from 0 to 20.
<span>X<=20
Y<=20
If the difference between their two numbers is less than 10, then Erik wins.
The difference between the two numbers can be written X-Y, or Y-X depending on which number (X or Y) is greater. But we do not know that. In order not to get negative value, we calculate absolute value of X-Y, written |X-Y| which will give positive value whether X is greater than Y or not.
If |X-Y|<10 Erik wins.
</span><span>If the difference between their two numbers is greater than 10, then Nita wins.
</span><span>If |X-Y|>10 Nita Wins
</span>
DONT OPEN THE ANSWER ABOVE ITS A VIRUS. i will give an answer in the comments though