Answer:
r(-1) = 6.31 and r(2) = -16.88
Step-by-step explanation:
* Lets read the problem and solve it
- Evaluate means find the value, so evaluate r(x) means find the value
of it at the given values of x
∵ r(x) = -0.21x³ + x² - 8.1x - 3
∵ x = -1 and x = 2
- Then find r(-1) by substitute x by -1 and find r(2) by substitute x by 2
# At x = -1
∴ r(-1) = -0.21(-1)³ + (-1)² - 8.1(-1) - 3
∴ r(-1) = -0.21(-1) + (1) - 8.1(-1) - 3
∴ r(-1) = 0.21 + 1 + 8.1 - 3
∴ r(-1) = 6.31
# At x = 2
∴ r(2) = -0.21(2)³ + (2)² - 8.1(2) - 3
∴ r(2) = -0.21(8) + (4) - 8.1(2) - 3
∴ r(2) = -1.68 + 4 - 16.2 - 3
∴ r(2) = -16.88
* r(-1) = 6.31 and r(2) = -16.88
Answer:
x=1 and y=4/5
Step-by-step explanation:
<u>Given system of equations</u>
3x+5y=7
5x+10y=13
<u />
<u>Multiply first equation by 2</u>
2(3x+5y)=2(7)
6x+10y=14
<u>Eliminate y-variable to get "x"</u>
6x+10y=14
<u>- 5x+10y=13</u>
x = 1
<u>Substitute x=1 into either equation and find "y"</u>
3x+5y=7
3(1)+5y=7
3+5y=7
5y=4
y=4/5
Therefore, x=1 and y=4/5
Answer:
0.7 is a decimal and 70/100 or 70% is the percentage for 35/50.
Step-by-step explanation:
Hope this helps!
15 + 2x - 4 = 9x + 11 - 7x
2x + 11 = 2x + 11
always true
2x + 3(4x - 1) = 2(5x + 3) + 4x
2x + 12x - 3 = 10x + 6 + 4x
14x - 3 = 14x + 6
never true
Answer:
The 4th one
Step-by-step explanation:
-3-(-8)=5
