Y-4X =3 ; 2x-3y=21
Y= 3+ 4x
2x -3( 3+4x)= 21
2x- 9- 12x= 21
-10x -9= 21
-10x -9+9= 21+9
-10x = 30
X= 30/-10= -3
Y= 3+4x = 3+ 4* (-3)= 3-12= -9
I prefer to use compatible numbers because by using this method it is easier to make a sum mentally. This is true because compatible numbers are close in value to the actual numbers. For a better understanding, let's take an example:
Suppose you have two numbers, namely 640 and 40. These two numbers are compatible for division because:
64 ÷ 4 = 16
So, we have used mental arithmetic to solve a more complex problem.
Okay, so to get the inverse function, you need to isolate the x first.
You can do this by multiplying by 4. Then, -2 to get just 3x and finally divide by 3 so that you just have x on its own. If we write this all out, we get (4x-2)/3.
Next, we need to substitute 24 into x's place. So, we have ((4x24)-2)/3. Then, we can just simplify. 4x24=96. 96-2=94. 94/3=32.6.
Hope this helps :)
2/5 or 0.4 Because only two of the five numbers are even or greater than 78
Hi there!
15 × 100 ÷ 60 = 25
So, 60% of 25 is 15.
Hope this helps!
