Answer:
50 of D and 10 of C
Step-by-step explanation:
First of all, put this data into 2 equations.
You sold 60 items, so C+D=60
C is $5 so we can represent it by 5C
D is $7 so we can represent it by 7D
You made $400 total from C and D, so 5C+7D=400
We can use simultaneous equations to solve this.
To eliminate one of these variables, we'll multiply the first one by 5 to make it 5C like the other.
5(C+D=60) (make sure you multiply both sides.)
so 5C+5D=300
5C+7D=400
Now we solve it:
5C-5C+7D-5D=400-300
7D-5D=100
2D=100
D=50
Now we can substitute this with one of the equations to find C
C+50=60
C=60-50
C=10
so, (10x5)+(50x7)=400
I think 1 sorry if it is wrong
Answer:
56
Step-by-step explanation:
x+x+8=104
2x=96
x=48
48+8=56
28.3 / 9 = 3.14444444......
3.14 round to 3
X^2(x)+5x(x)+6/x(x)+1(x)=1(x)
X^3+5x^2+6+x=x
X^3+5x^2+6=0
Use cube
X is approx -5.220181