BD = AC Given. BD cuts AC in half. That's what bisectors do.
BD = BD Reflexive property of a line (it is always equal to itself).
<ADB = <ADC = 90o
DB is perpendicular to AC Given.
<ADB + <ADC = 180o The two are supplementary.
Each angle = 90o Perpendicular means that one line meets another at 90o
2x = 180
x = 90o
Since each of the enclosed angles = 90, two have two triangles congruent by SAS <<<< Answer
9514 1404 393
Answer:
(x, y, z) = (-1, 0, -3)
Step-by-step explanation:
We notice that the coefficients of z are such that elimination of the z term from the equations is made easy.
Adding equations 1 and 2:
(2x -3y -2z) +(x +3y +2z) = (4) +(-7)
3x = -3
x = -1
Adding equations 2 and 3:
(x +3y +2z) +(-4x -4y -2z) = (-7) +(10)
-3x -y = 3
Substituting for x, we get ...
(-3)(-1) -y = 3
0 = y . . . . . . . . . . . add y-3 to both sides
Then z can be found from any equation. Substituting for x and y in the second equation gives ...
-1 +2z = -7
2z = -6 . . . . . add 1
z = -3 . . . . . .divide by 2
The solution is (x, y, z) = (-1, 0, -3).
Answer: 4. 78,020,008 4. Seventy-eight million, twenty thousand, eight
5. 20,011,012 5. 20,000,000 + 11,000 + 12
6. 50,000 7. 900 8. 70,000,000 9. 30,000,000
Step-by-step explanation:
