well, we know it's a rectangle, so that means the sides JK = IL and JI = KL, so
![\stackrel{JK}{3x+21}~~ = ~~\stackrel{IL}{6y}\implies 3(x+7)=6y\implies x+7=\cfrac{6y}{3} \\\\\\ x+7=2y\implies \boxed{x=2y-7} \\\\[-0.35em] ~\dotfill\\\\ \stackrel{JI}{6y-6}~~ = ~~\stackrel{KL}{2x+20}\implies 6(y-1)=2(x+10)\implies \cfrac{6(y-1)}{2}=x+10 \\\\\\ 3(y-1)=x+10\implies 3y-3=x+10\implies \stackrel{\textit{substituting from the 1st equation}}{3y-3=(2y-7)+10} \\\\\\ 3y-3=2y+3\implies y-3=3\implies \blacksquare~~ y=6 ~~\blacksquare ~\hfill \blacksquare~~ \stackrel{2(6)~~ - ~~7}{x=5} ~~\blacksquare](https://tex.z-dn.net/?f=%5Cstackrel%7BJK%7D%7B3x%2B21%7D~~%20%3D%20~~%5Cstackrel%7BIL%7D%7B6y%7D%5Cimplies%203%28x%2B7%29%3D6y%5Cimplies%20x%2B7%3D%5Ccfrac%7B6y%7D%7B3%7D%20%5C%5C%5C%5C%5C%5C%20x%2B7%3D2y%5Cimplies%20%5Cboxed%7Bx%3D2y-7%7D%20%5C%5C%5C%5C%5B-0.35em%5D%20~%5Cdotfill%5C%5C%5C%5C%20%5Cstackrel%7BJI%7D%7B6y-6%7D~~%20%3D%20~~%5Cstackrel%7BKL%7D%7B2x%2B20%7D%5Cimplies%206%28y-1%29%3D2%28x%2B10%29%5Cimplies%20%5Ccfrac%7B6%28y-1%29%7D%7B2%7D%3Dx%2B10%20%5C%5C%5C%5C%5C%5C%203%28y-1%29%3Dx%2B10%5Cimplies%203y-3%3Dx%2B10%5Cimplies%20%5Cstackrel%7B%5Ctextit%7Bsubstituting%20from%20the%201st%20equation%7D%7D%7B3y-3%3D%282y-7%29%2B10%7D%20%5C%5C%5C%5C%5C%5C%203y-3%3D2y%2B3%5Cimplies%20y-3%3D3%5Cimplies%20%5Cblacksquare~~%20y%3D6%20~~%5Cblacksquare%20~%5Chfill%20%5Cblacksquare~~%20%5Cstackrel%7B2%286%29~~%20-%20~~7%7D%7Bx%3D5%7D%20~~%5Cblacksquare)
Answer:
See below
Step-by-step explanation:
x(x-2y)-(y-x)2
Final result :
-y2
Step by step solution :
Step 1 :
Equation at the end of step 1 :
x • (x - 2y) - (y - x)2
Step 2 :
2.1 Evaluate : (y-x)2 = y2-2xy+x2
Final result :
-y2
Answer:
Step-by-step explanation: If Professor Lam grades 4 papers per hour, in 11 hours he will graded 44 papers. (11 x 4= 44). He had previously graded 6 papers giving him a total of 50 papers graded. His assistant can grade 5 papers per hour, thus it would take him 10 hours to grade the same amount of papers as Professor Lam. (10 x 5= 50) Thus: 11 hours Professor Lam 50 papers graded; 10 hours his assistant 50 papers graded.
Answer/Step-by-step explanation:
Let x = 4 (you and 3 friends)
Ticket cost per head = $5.50
Drink cost per head = $2.50
Popcorn cost per head = $4.00
<em>Expression representing total amount of money spent = $5.50(x) + $2.50(x) + $4.00(x)</em>
<em />
Evaluate the expression by plugging in the value of x = 4
Total amount of money spent = $5.50(4) + $2.50(4) + $4.00(4)
= $22 + $10 + $16 = $48
<em>Total amount of money spent = $48</em>