Answer:
x = 3
, y = 5
Step-by-step explanation:
Solve the following system:
{3 y - 7 x = -6 | (equation 1)
3 y - 3 x = 6 | (equation 2)
Subtract 3/7 × (equation 1) from equation 2:
{-(7 x) + 3 y = -6 | (equation 1)
0 x+(12 y)/7 = 60/7 | (equation 2)
Multiply equation 2 by 7/12:
{-(7 x) + 3 y = -6 | (equation 1)
0 x+y = 5 | (equation 2)
Subtract 3 × (equation 2) from equation 1:
{-(7 x)+0 y = -21 | (equation 1)
0 x+y = 5 | (equation 2)
Divide equation 1 by -7:
{x+0 y = 3 | (equation 1)
0 x+y = 5 | (equation 2)
Collect results:
Answer: {x = 3
, y = 5
Its a simultaneous equation:
lets make "x" the used games and "y" the new ones
4x + 2y = 84
6x + y = 78. (multiply this by 2 to cancel out y)
12x + 2y = 156
so now we subtract them:
12x - 4x = 156 - 84
x = 9
used games cost $9
new games cost 78 - 6(9) = $24
Janet has $120 but she already bought 3 NEW games so:
120 - 3(24) = $48 left
48/9 = how many used ones she can buy = 5. something
she can buy 5 used
Answer:
791.28
Step-by-step explanation:
1. 3.14*9²=254.34
2. 3.14*9*19=536.94
3. 536.94+254.34=791.28
Answer:
question 3: 1/3 question 4: 5/7 question 5: 2/3
4% means <span>4100</span> 'of' means multiply so:
<span>363.99⋅<span>4100</span></span> is <span>363.99⋅4</span> = 1455.96
<span>1455.96100</span> = 14.56 (rounded up)
<span>363.99+14.56=$378.55</span> to the nearest cent.