3. Solve the system of equations using linear combination. a + c = 9 8a + 4.5c = 58

Mathematics

2 answers:

sergij07 [2.7K]2 years ago

7 0

A+c=9 so a=9-c
8(9-c)=72-8c+4.5c=58
12.5c=58-72
12.5c=-14
c=-1.12

lana66690 [7]2 years ago

5 0

Hey I have posted a picture the method I use to solve simultaneous equations is change the sign and follow the new sign.
This involves changing the sign for the second equation and solving it

You might be interested in

What is 7 over 20 as a percentage

expeople1 [14]

7/20) * 100%
= 35%
= 0.3

4 0

2 years ago

Read 2 more answers

If s(x)=x-7 and t(x) =4x^2+3 which expression is equivalent to (t×s)(x)

marshall27 [118]

Answer:

$\large\boxed{(t\times s)(x)=4x^3-28x^2+3x-21}$

Step-by-step explanation:

$s(x)=x-7\\t(x)=4x^2+3\\\\(t\times s)(x)=t(x)\times s(x)\\\\\text{Substitute:}\\\\(t\times s)(x)=(4x^2+3)(x-7)\\\\\text{use FOIL:}\ (a+b)(c+d)=ac+ad+bc+bd\\\\(t\times s)(x)=(4x^2)(x)+(4x^2)(-7)+(3)(x)+(3)(-7)\\\\=4x^3-28x^2+3x-21$

8 0

3 years ago

Can someone please teach me how to add, subtract, multiply and divide negative numbers?

dedylja [7]

If both numbers are negative u add those up and ur answer will be a negative. so number one is negative 9.
if there is more positive ur answer will be a positive. so number 2 is 13.
number is more complicated so negative 3 +4 is 1 because u have more positive and u just subtract those then 1 minus 8 equals negative 7 and negative 7 minus 7 is 0. hope this helps

3 0

2 years ago

Read 2 more answers

Which statement is true? a,b,c or d

Brums [2.3K]

It might be d but i’m not sure

8 0

2 years ago

Calculate the average speed of a train that

lorasvet [3.4K]

Answer:

Step-by-step explanation:

4 0

2 years ago