5x + y = 27
substitute: 5x + 4x = 27
combine: 9x = 27
divide (by 9): x = 3
Answer:
4.875
Step-by-step explanation:
The mean is the average of all the numbers or all the numbers added up divided by how many numbers so
3+5+2+10+6+3+7+3=39 and there are 8 numbers so
39/8 is 4.875 or 4 7/8
4.875
Answer:
4 × ( 9 + 2z)
Step-by-step explanation:
36 + 8z = 4 × (9) + 4 × (2z) ; so here 4 is a common factor
= 4 × ( 9 + 2z)
we can also write it like this
36 + 8z = 2 × ( 18 + 4z)
B= 30
a2+b2=c2
72^2+b^2 = 78^2
5184+b^2 = 6084
b2 = 900
b = 30