Answer:
For 90 is having each containing both the 20 and10 for 2 boxes then the rest each a 20&10
For 60 is two 20s and two10
Step-by-step explanation:
Hope it helps
For 90:
9 10p coins
7 10p coins and 1 20p coin
5 10p coins and 2 20 p coins
3 10p coins and 3 20p coins
For 60:
6 10p coins
4 10p coins and 1 20p coin
2 10p coins and 2 20p coins
3 20p coins
do: first of first bracket x first of 2nd bracket
+( first of 1st bracket x 2nd of 2nd bracket)
+(2nd of 1st bracket x 1st of 2nd bracket)
+ (2nd of 1st bracket x 2nd of 2nd bracket)
== 10n -16n +20n+32= 14n+32
a 30 b -21
a 5x = 5(6)
= 30
b 3y = 3(-7)
= -21
