Equation 1. N+D=500
equation 2 5N+10D=3000
This is for equation 1
N=500-d
Substitute into equations 2 and solve for D
5N+10D=3000
5(500-D)+10D=3000
2500-5D+10D=3000
5D=500
D=100
Lets go back the equation 1
N=500-D
N=500-100
N=400
there are 400 Nickles and 100 Dimes
Answer: J
Step-by-step explanation:
J is the expression we would use to find "nine divided by five"
Whatever is inside the little box-looking thing (not sure how to describe it) is being divided by the number on the outside of the box-looking thing.
Answer:
$0.40 per minute
Step-by-step explanation:
You divide 6.40 by 16 to get 0.40.
To fact check this, I multiplied 0.40 by 16 and got 6.40.
Answer:
1) x=8, y=138
2) x=110
Step-by-step explanation:
Answer:
x = 1
y = -3
Step-by-step explanation:
cos(pi) = -1
so many ways :
sqrt(0.5/2) = sqrt(0.5/2 × 8/8) = sqrt(4/16)
= sqrt(0.5/2 × 18/18) = sqrt(9/36)
= sqrt(1/4) = 1/2
"nicest" approach (all integers) :
3x² = sqrt(9)
3x² = 3
x² = 3/3 = 1
x = 1
2y = sqrt(36)
2y = 6
y = 6/2 = 3
one of them has to be negative (because cos(pi) = -1), so it has to be y, because 3x² cannot be negative with real numbers.
so, y = -3
-1 × 3×1²/(2×-3) = sqrt(0.5/2) = 1/2
-1 × 3/-6 = 1/2
3/6 = 1/2
1/2 = 1/2
correct
