All categories

3 years ago

Which of these systems of equations has a solution of (6,−7)?

Mathematics

1 answer:

Damm [24]3 years ago

4 0

Answer:

x-2y=20

2x-y=19

You might be interested in

Make g the subject of the formula 3e + 4g = 7 + 9e

NISA [10]

Answer:

g=(7+9e-3e)/4

Step-by-step explanation:

3e+4g=7+9e

4g=7+9e-3e

g=(7+9e-3e)/4

3 0

3 years ago

Read 2 more answers

PLZZ HELP

9966 [12]

An arithmetic sequence would have a common difference between successive terms, not the case here.

A geometric sequence has a common ratio; let's check:

$\dfrac{1/2}{1/6} = 3$

$\dfrac{3/2}{1/2} = 3$

$\dfrac{9/2}{3/2} = 3$

That's a common ratio of 3 so as far as we can tell a geometric sequence.

Answer: geometric

3 0

3 years ago

Read 2 more answers

Simplify the expression. Use standard polynomial format. x(2x + 3) + (x - 3)(x - 4)

timofeeve [1]

Answer:

x(2x + 3) + (x - 3) (x - 4) = 3x²- 4x + 12

Step-by-step explanation:

Expand:

x(2x + 3): 2x² + 3x

2x² + 3x + (x - 3) (x - 4)

Expand:

(x - 3) (x - 4): x²- 7x + 12

2x² + 3x + x²- 7x + 12

Simplify:

2x² + 3x + x² - 7x + 12: 3x² - 4x + 12

= 3x² - 4x +12

5 0

3 years ago

Simplify: 2(8 - 2x4).

pentagon [3]

Answer:

2(8-8x)

Step-by-step explanation:

Distrubutive Property:

↓

A(B+C)=AB+AC

Multiply by the numbers from left to right.

4*2=8

Therefore the correct answer is 2(8-8x).

7 0

3 years ago

Read 2 more answers

Prove that:- (1-sinA)(1+sinA)÷(1+cosA)(1-cosA)=cot^2A

astraxan [27]

Answer:

see explanation

Step-by-step explanation:

Using the trigonometric identity

sin²x + cos²x = 1 , then

sin²x = 1 - cos²x and cos²x = 1 - sin²x

Consider the left side

$\frac{(1-sinA)(1 + sinA)}{(1+cosA)(1-cosA)}$ ← expand numerator/denominator using FOIL

= $\frac{1-sin^2A}{1-cos^2A}$

= $\frac{1-(1-cos^2A)}{1-(1-sin^2A)}$

= $\frac{1-1+cos^2A}{1-1+sin^2A}$

= $\frac{cos^2A}{sin^2A}$

= cot²A = right side , thus proven

6 0

3 years ago