The addition property of equality justifies this. You could also say that she simply subtracted 7, and then it would be the subtraction property of equality. This is the case because if you add or subtract (or multiply or divide) the same number on both sides of an equation, the equation will still be the same.
Hope it helps!
Answer:
10 spiders and 12 ants
Step-by-step explanation:
You need to create two equations
s = # of spiders
a = # of ants
s + a = 22 heads
since each spider and ant has one head
8s + 6a = 152 legs
since every spider has 8 legs and every ant has 6
s + a = 22 can be turned into s = 22 - a
now use substitution
8(22 - a) + 6a = 152
176 - 8a + 6a = 152
176 - 2a = 152
24 = 2a
a = 12
now that you have the number of ants you can solve for the number of spiders
s + a = 22
s + 12 = 22
s = 10
Answer: its c or 35
Step-by-step explanation: because at 10 salespeople its 40, so 9 salespeople is 35
