Answer:
7 years
Step-by-step explanation:
Given that:
Let Richard's age = x
Elder sister's age = 2x
Youngwr sister's age = x - 2
Product of sisters ages = 70
2x * (x - 2) = 70
2x² - 4x = 70
2x² - 4x - 70 = 0
x² - 2x - 35 = 0
x² - 7x + 5x - 35 = 0
x(x - 7) +5(x - 7) = 0
(x - 7) or (x + 5) = 0
x = 7 or x = - 5
X can't be negative
Hence, x = 7
Richard is 7 years
Answer:
see the explanation
Step-by-step explanation:
Let
x ----> the number of hours Eli worked
y ----> the number of hours Samantha worked
we know that
Eli and they ironed 400 shirts between them
so
----> equation A
Samantha worked 2 more hours than Eli
so
----> equation B
solve the system by substitution
substitute equation B in equation A
solve for x
Find the value of y
substitute the value of x in equation B
therefore
The number of hours Eli worked was 6 and the number of hours Samantha worked was 8
Answer:
Step-by-step explanation:
all you have to do is * 7 by 5 and divide by 2
