The value of k is -6
Step-by-step explanation:
The general form of the quadratic equation is y = ax² + bx + c
- The roots of the equation is the values of x when y = 0
- ax² + bx + c = 0, is used to find the roots
∵ 2x² + 11x = -k
- Add k to both sides
∴ 2x² + 11x + k = 0
∵ The roots of the quadratic equations is the values of x when y = 0
∵ 
is a root of the equation
- Substitute x by in the equation above to find k
∵ 2( )² + 11( ) + k = 0
∴ 2( 
) + 
+ k = 0
∴ + + k = 0
- Add the like terms
∵ + = 
= 6
∴ 6 + k = 0
- Subtract 6 from both sides
∴ k = -6
The value of k is -6
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Answer:
One pair of gloves costs $3.75.
Step-by-step explanation:
Systems of equations
x=hats y=gloves
2x+3y=28.25
x+y=12.25
2(12.25-y)+3y=28.25
24.5+y=28.25
y=3.75
Answer:
Joe worked 3 hours overtime.
Step-by-step explanation:
Let t = number of hours overworked
425 + 20 × t = 485
425 + 20t = 485
20t = 485 - 425
= 60
t = 3
Joe worked 3 hours over time.
Hope this helps :)
Answer:
(3, 3 )
Step-by-step explanation:
Given the 2 equations
3x - y = 6 → (1)
6x + y = 21 → (2)
Adding the 2 equations term by term will eliminate y, that is
(6x + 3x) + (y - y) = (21 + 6), that is
9x = 27 (divide both sides by 9 )
x = 3
Substitute x = 3 into either (1) or (2) and solve for y
Using (2), then
(6 × 3) + y = 21
18 + y = 21 ( subtract 18 from both sides )
y = 3
Solution is (3, 3 )
Answer:
7 pounds.
Step-by-step explanation:
3.60 for 3 pounds
1.20 per pound.
8.40/1.20 = 7 pounds
