Answer:
d
Step-by-step explanation:
Circles with the same centre are concentric circles
You take alll the answers and just divide each one
Let the cost of 1 notebook be x and the cost of 1 binder be y.
4 notebooks and 3 binders would cost 23.5
Therefore, 4x + 3y = 23.5 (1)
7 notebooks and 6 binders would cost 44.5
Therefore, 7x + 6y = 44.5 (2)
Multiply the first equation by 2.
8x + 6y = 47 (3)
(3) - (2) gives
x = 2.5
Substitute the value of x in (1), we get,
4(2.5) + 3y = 23.5
10 + 3y = 23.5
3y = 23.5 - 10
3y = 13.5
y = 13.5/3
y = 4.5
Hence, cost of 5 notebooks and 3 binders is:
5x + 3y = 5(2.5) + 3(4.5)
= 12.5 + 13.5
= 26
Hence, cost of 5 notebooks and 3 binders is $26.
Answer:
x = (180 - [71 + 9]) ÷ 2
Step-by-step explanation:
71 + 9 = 80
180 - 80 = 100°
100° ÷ 2 = 50°
Step-by-step explanation:
a) 1.16× 10^-6
standard form should be less than 10. therefore, count decimal places from where the decimal point is located to the right until you reach a number less than 10 ....count the number of shifts in the above is 6 shifts to the right. when moving to the right, power will be negative.(-6)
1.157/1.16 ×10^-6
b) 6.79 × 10^10
67890000000....count till a number less than 10.there will be 10 shifts to the left. the 10 will be your power,(positive) since u r moving to the left exponent is positive
6.789/6.79 × 10^10