Step-by-step explanation:
1) The question reads that
2(x+3)=20
So here we are finding x
We need to multiply the 2 by the ones in the bracket which is the (x+3)
So 2 multiplied by x is 2x
We didn't add the x and the 3 because a variable and a number can't be added, a number and a variable which is the letter can only be multiplied.
And then we also multiply 2 by 3 which is going to be;
2(3)
6
So it's going to be;
2x+6=20
So now, we group like terms;
2x=20-6(We have -6 because any positive number which crosses an equal sign becomes a negative and when a negative number crosses an equal sign it becomes a positive which is represented by +
2x=14
So now we subtracted 6 from the 20 giving us 14
So now we proceed to divide both sides by 2 to obtain the value of x
So 14 can be divided by 2,
7 times so;
x=7
2) So this question reads;
10x-3(2x+2)=30
With this we are also finding x
So here, we multiply the -3 by the 2x and the +2
So;
-3×2x=-6x
And
-3×2=-6
So now we have;
10x-6x-6=30
So here we can choose to group like terms of subtract the 6x from the 10x right away but grouping would be better so we are going to group which is going to be;
10x-6x=30+6
4x=36
So now we divide both sides by 4 to find the x
and 36 can be divided by 4, 9 times.
So;
x=9