Answer:
-765
Step-by-step explanation:
-2-7 * 109
-2 - 763
-765
Answer:
2.3 by 10^7
Step-by-step explanation:
We want this rewritten in the form 2.3*10^n.
To get the decimal point in 23,000,000 between the 2 and 3, we must move it 7 places to the left, and then compensate for this by multiplying 2.3 by 10^7.
Let 11x + 15y + 23 = 0 be equation (1)
And 7x - 2y - 20 = 0 be equation (2)
Multiply equation (1) by 2:
22x + 30y + 46 = 0
Multiply equation (2) by 15:
105x - 30y - 300 = 0
Add equations (1) and (2):
22x + 105x + 30y - 30y + 46 - 300 = 0
127x - 254 = 0
127x = 254
x = 254/127
[x = 2]
Substitute x = 2 in equation (1) to find y:
11(2) + 15y + 23 = 0
22 + 15y + 23 = 0
15y + 45 = 0
15y = -45
y = -45/15
y = -3
Therefore, x = 2 and y = -3.
