Given that the width of the rectangular piccture is:

Where "l" is the length of the picture.
You know that the perimeter is:

The formula for calculating the perimeter of a rectangle is:

Where "l" is the length and "w" is the width.
Therefore, you can substitute the perimeter and the width into the formula, in order to find "l":

Now you can solve for "l":





Hence, the answer is:
Answer:
younger sibling = 29 years
older sibling = 35 years
Step-by-step explanation:
Let
x = younger sibling
y = older sibling
x + y = 64 (1)
The older sibling was born 6 years before their young sibling
x = y - 6 (2)
Substitute x = y - 6 into (1)
x + y = 64
y - 6 + y = 64
2y = 64 + 6
2y = 70
y = 70/2
y = 35 years
Substitute y = 35 into (2)
x = y - 6
x = 35 - 6
x = 29 years
Answer:
Subtract both sides by 7
Step-by-step explanation:
We have to make sure that we isolate the x term first. So we must subtract 7 from both sides.