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:
slope = 4
Step-by-step explanation:
Calculate the slope m using the slope formula
m = 
with (x₁, y₁ ) = (0, 0) and (x₂, y₂ ) = (3, 12) ← 2 points on the line
m =
=
= 4
Answer:
x = 3/2 | y = -3
Step-by-step explanation:
Given equations:
- y = 2x - 6. . . .(i)
- y = -4x + 3. . . . (ii)
Substituting from equation (i) for y:
==> 2x - 6 = -4x + 3
==> 2x + 4x = 6 + 3
==> 6x = 9
<em>dividing both </em><em>sides by 3</em><em>:</em>
==> 2x = 3
==> x = 3/2
Substituting 3/2 for x in equation (i):
==> y = 2(3/2) - 6
==> y = 3 - 6
==> y = -3
Answer:
-1
Step-by-step explanation:
The common difference is the constant amount of change between the numbers in an arithmetic sequence.
To find the common difference, you take the last term and subtract it by the previous term.

<span>-9 divided by 5/8 equals
-9 / (5/8) <---</span><span>Turn the second </span>fraction<span> upside down, then multiply.
= -9 * 8/5
= -72/5
= -14 2/5
= -14.4</span>