Hey! a+5=7 means that a is the variable, while seven is the answer. My technique is like this: 7-5=2 You need to subtract the numbers you already have. This only works for addition! Hope this helps :) !
Y - x - 3 = 0
y = x + 3
y = x^2 - x - 12
x + 3 = x^2 - x - 12
x^2 - x - 12 - x - 3 = 0
x^2 - 2x - 15 = 0
(x - 5)(x + 3) = 0
x - 5 = 0 y = x + 3
x = 5 y = 5 + 3
y = 8
x + 3 = 0 y = x + 3
x = -3 y = -3 + 3
y = 0
so ur solutions are : (5,8) and (-3,0)
Answer:

Step-by-step explanation:
The value would be 4.
First, you have to do 4 + 3 because it's in parenteces. This equals 7
Secondly, you have to do 2 x 7, which is 14.
Last you have to do 18 - 14 which is 4.
It’s simple you just multiply all three numbers 20*3*4=240