#6
D. 3.0 x 10^8
#7
A. y = 3.5x + 7
#8
B. 5
Answer:
(0,3) and (7,0) are solutions.
Step-by-step explanation:
In a pair of coordinates, they are always listed as (x,y). Since this is the case, you plug in each coordinate to their respective places.
For (0,3)
3(0) + 7(3) = 21
0 + 21 = 21
For (7,0)
3(7) + 7(0) = 21
21 + 0 = 21
To double check that (1,2) isn't a solution:
3(1) + 7(2) = 21
3 + 14 = 21
17 = 21 X
This doesn't work.
Marking as Brainliest is much appreciated.
Answer:
x = 10/9
Step-by-step explanation:
Solve for x:
(4 x)/5 + 4/3 = 2 x
Put each term in (4 x)/5 + 4/3 over the common denominator 15: (4 x)/5 + 4/3 = (12 x)/15 + 20/15:
(12 x)/15 + 20/15 = 2 x
(12 x)/15 + 20/15 = (12 x + 20)/15:
(12 x + 20)/15 = 2 x
Multiply both sides by 15:
(15 (12 x + 20))/15 = 15×2 x
(15 (12 x + 20))/15 = 15/15×(12 x + 20) = 12 x + 20:
12 x + 20 = 15×2 x
15×2 = 30:
12 x + 20 = 30 x
Subtract 30 x from both sides:
(12 x - 30 x) + 20 = 30 x - 30 x
12 x - 30 x = -18 x:
-18 x + 20 = 30 x - 30 x
30 x - 30 x = 0:
20 - 18 x = 0
Subtract 20 from both sides:
(20 - 20) - 18 x = -20
20 - 20 = 0:
-18 x = -20
Divide both sides of -18 x = -20 by -18:
(-18 x)/(-18) = (-20)/(-18)
(-18)/(-18) = 1:
x = (-20)/(-18)
The gcd of 20 and -18 is 2, so (-20)/(-18) = (-(2×10))/(2 (-9)) = 2/2×(-10)/(-9) = (-10)/(-9):
x = (-10)/(-9)
Multiply numerator and denominator of (-10)/(-9) by -1:
Answer: x = 10/9
