Y=42 Y=?
X=6 X=3
cross multiply
so 42times3=6timesY
126=6Y
Y=126 divided by 6
=21
X² - 10x = 46
10/2 = 5; 5²+ 25 add 25 to both sides
x² - 10x + 25 = 46 + 25
so the number you have to add to complete the square is 25.
Answer:


Step-by-step explanation: