Answer:
<u>The sum of their ages now is 13</u>
Step-by-step explanation:
Dally's age = x
Dilly's age = x - 7
In 4 years time Dilly will be half Dally’s age, therefore:
Dilly's age plus four equals to half of Dally’s age plus four,
replacing with the values and variables we know:
x - 7 + 4 = (x + 4) /2
x - 3 = (x + 4) /2
2x - 6 = x + 4 (Multiplying by 2 at both sides)
2x - x = 4 + 6 (Like terms)
x = 10 ⇒ x - 7 = 3
<u>The sum of their ages now is 13 (10 + 3)</u>
Answer:
4
Step-by-step explanation:
hope it helps ;)
2x-y=7
y=2x+3
Substitute (2x+3) in for y in the first equation
2x-(2x+3)=7
2x-2x-3=7
-3=7
Becuase -3 does not equal 7 the answer is no solution
Answer:
d = -8
Step-by-step explanation:
Isolate the variable, d. Note the equal sign, what you do to one side, you do to the other. Divide -4 from both sides of the equation:
d = -8 is your answer.
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Step-by-step explanation:
3/6=k/7
cross multiply then
6k=21
divide by the coefficient of k
k=3.5
