Solve the system (x-1)²+(y-2)²=2² and y=2x+2.

  (x, y) = (-0.6, 0.8)  or  (1, 4)

Step-by-step explanation:

Use the second equation to substitute for y in the first.

 (x -1)² +((2x +2) -2)² = 4

  x -2x +1 + 4x² = 4 . . . . . . . eliminate parentheses

  5x² -2x -3 = 0 . . . . . . . . . . subtract 4, collect terms

Now we can rearrange the middle term to ease factoring by grouping.

  (5x² -5x) +(3x -3) = 0

  5x(x -1) +3(x -1) = 0

  (5x +3)(x -1) = 0

The values of x that make these factors zero are ...

  x = -3/5, x = 1

The corresponding values of y are ...

  y = 2(-3/5)+2 = 4/5 . . . . for x = -3/5

  y = 2(1) +2 = 4 . . . . . . . . for x = 1

The solutions are: (x, y) = (-3/5, 4/5) or (1, 4).

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A graphing calculator verifies these solutions.

answer:   28.56 feet (approx)

step-by-step explanation:

since, triangle abc has measure of angle c equal to 55 degrees, measure of angle abc equal to 90 degrees, and length of bc equal to 20 feet.

we have to find out the measurement of segment ab.

therefore, tan 55° =

but bc = 20 feet.

⇒ tan 55 ° =  

⇒ ab = 20 × tan 55 °

⇒ ab = 20 × 1.42814800674

⇒ ab = 28.5629601348   ≈ 28.56 feet