Answer:
The amount we have to deposit in a savings account x = $ 17777.78
Step-by-step explanation:
Amount = $ 20000
R = 2.5 %
Time = 5 years
Take principal amount = x
Simple interest earned in five years
S.I. = 
------- (1)
We know hat total amount is given by
Total amount = principal amount + simple interest
A = x + S.I.
Given that the total amount after 5 years is = $ 20000
x = $ 17777.78
This is the amount we have to deposit in a savings account.
Answer:
The 8 should have remained positive.
Step-by-step explanation:
8-(-2)=8+2=10
Two negatives make a positive so 8-(-2) will turn into 8+2.
Laura was wrong because she thought the 8 turned to a negative but that makes no sense.
Answer:
Option D.
Step-by-step explanation:
The given points are (-2,0), (0,1), (0,-4) and (3,0).
In each ordered pair first element is x-coordinate and second is y-coordinate.
For 4 points, the table must have 2 columns and 4 rows.
So, the required table of values is
x y
-2 0
0 -4
0 1
3 0
Therefore, the correct option is D.
The system is:
i) <span>2x – 3y – 2z = 4
ii) </span><span>x + 3y + 2z = –7
</span>iii) <span>–4x – 4y – 2z = 10
the last equation can be simplified, by dividing by -2,
thus we have:
</span>i) 2x – 3y – 2z = 4
ii) x + 3y + 2z = –7
iii) 2x +2y +z = -5
The procedure to solve the system is as follows:
first use any pairs of 2 equations (for example i and ii, i and iii) and equalize them by using one of the variables:
i) 2x – 3y – 2z = 4
iii) 2x +2y +z = -5
2x can be written as 3y+2z+4 from the first equation, and -2y-z-5 from the third equation.
Equalize:
3y+2z+4=-2y-z-5, group common terms:
5y+3z=-9
similarly, using i and ii, eliminate x:
i) 2x – 3y – 2z = 4
ii) x + 3y + 2z = –7
multiply the second equation by 2:
i) 2x – 3y – 2z = 4
ii) 2x + 6y + 4z = –14
thus 2x=3y+2z+4 from i and 2x=-6y-4z-14 from ii:
3y+2z+4=-6y-4z-14
9y+6z=-18
So we get 2 equations with variables y and z:
a) 5y+3z=-9
b) 9y+6z=-18
now the aim of the method is clear: We eliminate one of the variables, creating a system of 2 linear equations with 2 variables, which we can solve by any of the standard methods.
Let's use elimination method, multiply the equation a by -2:
a) -10y-6z=18
b) 9y+6z=-18
------------------------ add the equations:
-10y+9y-6z+6z=18-18
-y=0
y=0,
thus :
9y+6z=-18
0+6z=-18
z=-3
Finally to find x, use any of the equations i, ii or iii:
<span>2x – 3y – 2z = 4
</span>
<span>2x – 3*0 – 2(-3) = 4
2x+6=4
2x=-2
x=-1
Solution: (x, y, z) = (-1, 0, -3 )
Remark: it is always a good attitude to check the answer, because often calculations mistakes can be made:
check by substituting x=-1, y=0, z=-3 in each of the 3 equations and see that for these numbers the equalities hold.</span>
Answer:
f(7) = -23
Step-by-step explanation:
f(x) = -3x - 2
f(7) = -3(7) - 2
f(7) = -21 - 2 = -23
