D. (8, -22) is the correct answer
Answer:
19
Step-by-step explanation:
51-(16)x2
16x2=32
51-32=19
Answer:
x = -0.6
y = 2.2
z = 2
Step-by-step explanation:
2x + y - 2z = -3
x + 3y - z = 4
3x + 4y - z = 5
Rewrite the system in matrix form and solve it by Gaussian Elimination (Gauss-Jordan elimination)
2 1 -2 -3
1 3 -1 4
3 4 -1 5
R1 / 2 → R1 (divide the 1 row by 2)
1 0.5 -1 -1.5
1 3 -1 4
3 4 -1 5
R2 - 1 R1 → R2 (multiply 1 row by 1 and subtract it from 2 row); R3 - 3 R1 → R3 (multiply 1 row by 3 and subtract it from 3 row)
1 0.5 -1 -1.5
0 2.5 0 5.5
0 2.5 2 9.5
R2 / 2.5 → R2 (divide the 2 row by 2.5)
1 0.5 -1 -1.5
0 1 0 2.2
0 2.5 2 9.5
R1 - 0.5 R2 → R1 (multiply 2 row by 0.5 and subtract it from 1 row); R3 - 2.5 R2 → R3 (multiply 2 row by 2.5 and subtract it from 3 row)
1 0 -1 -2.6
0 1 0 2.2
0 0 2 4
R3 / 2 → R3 (divide the 3 row by 2)
1 0 -1 -2.6
0 1 0 2.2
0 0 1 2
R1 + 1 R3 → R1 (multiply 3 row by 1 and add it to 1 row)
1 0 0 -0.6
0 1 0 2.2
0 0 1 2
x = -0.6
y = 2.2
z = 2
Answer:
DB = CA (Proved)
Step-by-step explanation:
Statement 1.
∠D = ∠C, M is the midpoint of DC and ∠1 = ∠2
Reason 1.
Given
Statement 2.
Between Δ DBM and Δ CAM,
(i) DM = CM,
(ii) ∠D = ∠C and
(iii) ∠DMB = ∠CMA
Reason 2.
(i) given
(ii) given and
(iii) ∠ DMB = ∠1 + ∠AMB and ∠CMA = ∠2 + ∠AMB
Since ∠1 = ∠2, so, ∠DMB = ∠CMA.
Statement 3.
Δ DBM ≅ Δ CAM
Reason 3.
By angle-side-angle rule.
Statement 4.
DB = CA
Reason 4.
Corresponding sides of two congruent triangles. (Answer)
Y= kx (k being a constant)
10= k × 4 k=5/2
y= 5x/2 The answer is C.