I do t really know how to do this pls help

for number 5 Subtract 18 from both sides of the equation

4+18−18=30−18

for number 1 Subtract 7 from both sides of the equation

so number 3 subtract 3 from each side and so on hope it helps

im not sure how to explain it but--

for example.. the first one

1) y + 7 = 12

first, you subtract 7 from both sides

so-- you'll subtract 7-7 on the left and 12-7 from the right

now, you have y by itself since 7-7 = 0

y = 12-7, or y = 5

also its important to note that when the equation is like 2) and uses subtraction (x-4) instead of addition (y +7)-- then you add to both sides

so for 2)-- you'd add 4 to both sides for 4 to cancel out to equal 0

your goal is always to isolate the variable on one side