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
All<span> of them </span>have <span>four sides, are coplanar, </span>have<span> two diagonals, and the sum of their four interior angles equals 360 degrees.</span>
Step-by-step explanation:
Opposite angles in a cyclic quadrilateral are supplementary.
Therefore 3c = 4d = 180°, c = 60° and d = 45°.