7n-4=31
7n=31-4
7n=27
n=27/7
:n=3
It’s equation and it’s really easy to solve
Answer:
D = 4, Z = 24
Step-by-step explanation:
6D+3Z = 96
5D+4Z = 116
multiply top by 5 and bottom by -6
top equation = 30D+15Z = 480
bottom equation = -30D-24Z = -696
Cancel 30D and -30 D
top equation = 15Z = 480
Bottom equation = -24Z = -696
15Z - 24 Z = 480 - 696
-9Z = 216
Z = 216/9
Z = 24
Now that we have the value of Z, we can substitute it in any equation to find D
6D + 3(24) = 96
6D + 72 = 96
6D = 96 - 72
6D = 24
D = 24/6
D = 4
Because u r adding irrational to rational its like if u add a whole number to a negative number u get deeper into negatives in this case irrational is the negative and rational is the whole<span />
Answer:
19.53
Step-by-step explanation:
First let's find the new price of the backpack:
40% of 29.99 is
29.99 * 0.40 = 11.99
So the new price of the backpack is
29.99 - 11.99 = 18.00
Now let's find the price with tax
8.5% of 18.00 is
18.00 * 0.085 = 1.53
So the cost of the backpack is
18.00 + 1.53 = $19.53
Answer:
384 cm²
Step-by-step explanation:
Since it is a square pyramid, the total surface area of the pyramid is the area of its square base plus the area of its 4 triangular faces.
Area of a triangular face
= ½ ×12 ×10
= 60 cm²
Base area of pyramid
= 12 ×12
= 144 cm²
∴ Surface area of pyramid
= 4(60) +144
= 240 +144
= 384 cm²
