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.
Well right off the bat, I can see a good reason why it should boggle.
If (x+y)=6 and (x-y)=2, then (x+y)(x-y) would be 12. It can't be 20.
The first 4 lines on the paper are inconsistent, so the question in the 5th line can't be calculated.
Another possible source of uncertainty (for us, anyway) is the remarkable similarity between the way you write ' Y ' and the way you write ' 4 ' . For example, look at the ' Y⁴ ' (I think ...) in the last line.
Answer:
x = ± 
Step-by-step explanation:
Given
x² - 7 = 0 ( add 7 to both sides )
x² = 7 ( take the square root of both sides )
x = ±
