Solve the following simultaneous equations using an appropriate method. a) 7x + 3y = 16
y = 4x - 1

b) 2x + y = 8
4x + 3y = 16

c) -3x + 2y = 19
4x + 5y = 13

d) -3x + 7y = 9
4x - 3y = 7

e) -4x + 5y = -7
x = 23 - 3y

f) y = -x
y = -2/5x - 1/5

Answers

Answer 1
Answer:

Good evening ,

Look at the photo below for the answer.

:)

Answer 2
Answer:

Answer:

a) x = 1 , y = 3

Step-by-step explanation:

a) 7x + 3y = 16

y = 4x - 1

or

3y + 7x = 16 ... (i)

y - 4x = -1 ... (ii)

Solving the simultaneous equation by substitution;

Equation (ii) tells us that y = 4x - 1

Substituting that in (i) gives;

3(4x - 1) + 7x = 16

12x - 3 + 7x = 16

19x = 16 + 3 = 19

x = (19)/(19) = 1

y = 4(1) - 1 = 3


Related Questions

The number of adult passengers on a bus (excluding the driver) is three times the number of children. If there are a adult passengers on the bus, which expression shows the total number of people on the bus, including the driver?
Is 27/51 equal to 18/34
The height (h metres) and age (a years) of a tree are related by the following inequality: h < 4a – 3 for values of a between 1 and 10 Which pair of values satisfy this inequality? a. h = 2 and a = 1 b. h = 6 and a = 2 c. h = 10 and a = 3 d. h = 20 and a = 6
ariana has 2/3 quart of milk. she uses 3/4 of it in a recipe. how much milk did ariana use in her recipe?
Find the least common denominator (LCD) for the fractions. 1/12 and 3/4                                   A. 12       B. 4                                                  C. 16                                                  D. 48

12 gallons of water fill a tank to 3/4 capacity.If the tank is then filled to capacity, how many half-gallon bottles con be filled with the water in the tank?

Answers


We need to find out how many gallons will fill the whole tank

we first write 3/4 into its decimal fraction. 3/4 = 0.75.

Now we form an equation

0.75 = 12

    1 = x     (where x is he number of gallons needed to fill whole tank)

Simplify the equation:

0.75 × x = 12 × 1

0.75x = 12

       x = 12 / 0.75

        x = 16

It will take 16 gallons to fill whole tank to capacity.

Half gallon bottles that can be filled  from the tank are:16 x 2 = 32

So 32 half gallon bottles can be filled from the full tank.



Timothy makes a round chocolate cake. She wants to put a cream layer on the cake.If the cake is 6 cm in diameter, how many square cm of cream layer does she need to put on the chocolate cake?

Answers

This is asking for the area of the cake. I believe the formula is a=pi r^2

mick paid $2.94 in sales tax on an item that cost $42.00 before tax. At that rate, how much would he pay in sales tax for an item that costs $58.00 before tax?

Answers

Amount of sales tax paid on an item that cost $42.00 is $2.94.

Rate of sales tax paid = 2.94÷42 =0.07 = 7%.

Rate of sales tax paid by Mick is 7%. The question is asking is to find the sales tax he will pay on an item that costs $58 before tax.

Sales Tax paid by Mick on an item costing $58.00 is 7% of $58.00 =0.07 of 58=4.06.

Sales tax paid for an item that costs $58.00 before tax is $4.06.

$62.06

2.94 / 42 = .07 so the sales tax is 7%

Multiply .07 * 58 (you get 4.06) and then add it to 58

Estimate the sum of 299 and 388

Answers

Hello Its 700 Glad To Help! :)

What is a statement that is true for any number or variable

Answers

•A variable is a letter that represents a unknown number.
•If a variable is is alone. No matter what it has a 1 in front of it.

The fraction 8/9 is equivalent to what percent round your percent to the nearest tenth

Answers

O.888888
Rounded to the nearest 10
O.890