TERM 2: WEEK 8 CLASSWORK 1
1.
Solve the simultaneous equations using elimination method​
4x - 3y = 1
x + 3y = 19c
a.​

9514 1404 393

  (x, y) = (4, 5)

Step-by-step explanation:

We notice that the coefficients of y are opposites, so we can eliminate y by adding the two equations together.

  (4x -3y) +(x +3y) = (1) +(19)

  5x = 20 . . . . . . simplify

  x = 4 . . . . . . . . .divide by 5

Substituting into the second equation gives ...

  4 +3y = 19

  3y = 15 . . . . . . . subtract 4

  y = 5 . . . . . . . . . divide by 3

The solution is (x, y) = (4, 5).

area of part 1:

a1=base*height/2=(8+2)*(8-2-2-1)/2=10*3/2=15 ft^2

area of part 2:

a2=length*width=(8+2)*1=10 ft2

area of part 3:

a3=length*width=8*2=16 ft2

total shaded area : a1+a2+a3=41 ft2

total area of the reactangle : a=16*8=128 ft2

total area of the nonshaded region : 128-41=87 ft2