<u>Answer</u>:
Therefore has one solution.
<u>explanation</u>:
Given equations:
6x + y = -7
-24x -7y = 25
Make y the subject:
6x + y = -7
y = -7 - 6x ..............equation 1
-24x -7y = 25
-7y = 25 + 24x
y = (25 + 24x)/-7 ..........equation 2
Solve them simultaneously:
(25 + 24x)/-7 = -7 - 6x
25 + 24x = -7 (-7 - 6x)
25 + 24x = 49 + 42x
42x - 24x = 25- 42
18x = -24
x = 
Then y is:
y = -7 - 6x
y = -7 - 6( )
y = 1
Has one separate value of x and y: ( , 1 ); so it has one solution.
Dog weigh: 23
cat weigh: 5/8 dogs weigh
so..
23x5/8 = 115/8
So, the subtraction looks like this:
223
-119
_______
The reason why combining place values here is necessary is that 3 is less than 9 (so I can't just substract in the one's place without going to negative numbers)
so we combine the ones and tens places and substract the whole: 23-19 is four!
223
-119
_______
04
and then we continue
223
-119
_______
204
and that's the result!
20 • 12 is 240
1/2 • 12 • 4 is 24
so 264
