Answer:
Zero's
Step-by-step explanation:
Find the total cost of producing 5 widgets. Widget Wonders produces widgets. They have found that the cost, c(x), of making x widgets is a quadratic function in terms of x. The company also discovered that it costs $15.50 to produce 3 widgets, $23.50 to produce 7 widgets, and $56 to produce 12 widgets.
OK...so we have
a(7)^2 + b(7) + c = 23.50 → 49a + 7b + c = 23.50 (1)
a(3)^2 + b(3) + c = 15.50 → 9a + 3b + c = 15.50 subtracting the second equation from the first, we have
40a + 4b = 8 → 10a + b = 2 (2)
Also
a(12)^2 + b(12) + c = 56 → 144a + 12b + c = 56 and subtracting (1) from this gives us
95a + 5b = 32.50
And using(2) we have
95a + 5b = 32.50 (3)
10a + b = 2.00 multiplying the second equation by -5 and adding this to (3) ,we have
45a = 22.50 divide both sides by 45 and a = 1/2 and using (2) to find b, we have
10(1/2) + b = 2
5 + b = 2 b = -3
And we can use 9a + 3b + c = 15.50 to find "c"
9(1/2) + 3(-3) + c = 15.50
9/2 - 9 + c = 15.50
-4.5 + c = 15.50
c = 20
So our function is
c(x) = (1/2)x^2 - (3)x + 20
And the cost to produce 5 widgets is = $17.50
135 because
15x1=15 15x7=105
15x2=30 15x8=120
15x3=45 15x9=135
15x4=60 15x10=150
15x5=75 15x11=165
15x6=90 15x12=190
Answer:
Step-by-step explanation:
If the equations are true, they can be solved simultaneously.
Consider 2x-10y=-1 as Eq1 and 5x+6y=4 as Eq2
Multiplying Eq1 with 3 and Eq2 with 5 we get,
6x-30y=-3 -- Eq3 and 25x+30y=20 -- Eq4
Adding Eq3 and Eq4,
31x=17 Therefore, x=17/31
Plugin x=17/31 in Eq3,
6(17/31)-30y=-3 --- y=13/62
Plug In values of x and y in 7x-4y we get,
7(17/31)-4(13/62) = 3
So the value of 7x-4y = 3.