Answer:
a quadrilateral is a four sided shape that has four straight sides
Answer:
[7-2x+5y-(x-y) -[5x+3y-7]
= 7-2x+5y-x+y-5x-3y+7
=7+7-2x-x-5x+5y+y-3y
=14-8x+3y
=-8x+3y+14
Step-by-step explanation:
First let’s express the total number of marbles as such:
y(yellow marbles) + r(red marbles)=23; y+r=23
now let’s express the relation of yellow marbles to red marbles:
y=2r(2 times red marbles) - 4(4 less marbles); y=2r-4
since we figured out what y equals, we can plug into the first equation we created:
(2r-4)+r=23
now solve for r:
2r-4+r=23
combine like terms
3r-4=23
add 4 to both sides
3r=27
divide both side by 3
r=9
plug r back into first equation and solve for y:
y+9=23
subtract 9
y=14
there are 9 red marbles and 14 yellow marbles!
