Answer:
15
Step-by-step explanation:
Rate of change or slope or gradient of a line passes two points (x1, y1) and (x2, y2) could be calculated by:
(y2 - y1)/(x2 - x1)
=> Rate of change of the line passing (1,15) and (3,45):
(45 - 15)/(3 - 1) = 30/2 = 15
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>
I think it'd be 10in. If you cut it into three parts, where the bottom is sectioned off from the other two rectangles, the two rectangles on the side both have an area of 3in, so together they'd be 6in. The rectangle on the bottom has a length of 4 and a width of 1, so it'd be 4in... add those together and get 10in. Hope this helps
