13 + 21 = 13- -21
The minus sign and negative cancel each other out.
<span>y-2x=-6 and 5x-y=9
step 1: isolate y in the first equation
y = 2x - 6
step 2: substitute the y value on the 2th equation:
5x-(2x-6)=9
step 3: solve the present equation:
5x - 2x + 6 = 9
3x = 9-6
3x = 3
x = 1
step 4: get the y value by replacing the value of x in </span>y = 2x - 6:
<span>
y = 2*1 - 6
y = 2 - 6
y = -4
S={1, -4}
</span>
The simplest ratio is 1/3. Equivalent ratios would be 3/9 and 5/15.
I believe you have to do a cross product formula.
2174/x = 28.19/100
A = -11
B= -12
This is because of how calculations work in negatives. Because they are both negative they work similarly to addition
