First, let's multiply the first equation by two on the both sides:
<span>8x + 7y = 39 /2
</span>⇒ 16x + 14y = 78
Now, the system is:
<span>16x + 14y = 78
</span><span>4x – 14y = –68
</span>
After adding this up in the column:
(16x + 4x) + (14y - 14y) = 78 - 68
20x = 10
⇒ x = 10/20 = 1/2
y can be calculated by replacin the x:
<span>8x + 7y = 39
</span>⇒ 8 · 1/2 + 7y = 39
4 + 7y = 39
7y = 39 - 4
7y = 35
⇒ y = 35 ÷ 7 = 5
Answer:
The longer piece will be 10 feet long.
Step-by-step explanation:
16 - 10 is 6
10 is 4 more than 6
therefore the longer piece will be 10 feet long
Answer:
83.2 cm^2
Step-by-step explanation:
To solve this we're going to find the area of the bigger triangle (the shaded and unshaded parts together) and then the area of the smaller triangle (the unshaded part) and then subtract that from the area of the bigger triangle. We're going to use the equation: Area=1/2 x base x height. So the base of the big triangle is 16, and the height is (10.4+8.6 = 19). Put into the equation this looks like this: Area=1/2 x 16 x 19, so by multiplying we find that the area is 152 cm^2. Next we find the small triangle's area, Area=1/2 x 16 x 8.6, so the area is 68.8. Then to find the area of the shaded part, we subtract the unshaded area (68.8) from the whole area (152), 152-68.8=83.2.
Answer:
9 tables
Step-by-step explanation:
5 × 1.8 = 9
to find how many tables he made you have to multiply the number he made by 1, then .(whatever the percent is)