All categories

2 years ago

X=2y-47x+5y=-66 what is the x- value

Mathematics

1 answer:

Gwar [14]2 years ago

5 0

Answer:

x = -8

Step-by-step explanation:

x = 2y - 4 --- Equation 1

7x + 5y = -66 --- Equation 2

I will be using the substitution method to solve this.

Substitute x = 2y - 4 into Equation 2:

7x + 5y = -66

7(2y - 4) + 5y = -66

Evaluate.

14y - 28 + 5y = -66

Evaluate like terms.

19y - 28 = -66

Isolate 19y.

19y = -66 + 28

= -38

Find y.

y = -38 ÷ 19

y = -2 --- Equation 3

Substitute y = -2 into Equation 1:

x = 2y - 4

x = 2(-2) - 4

Evaluate.

x = -4 - 4

x = -8

You might be interested in

Please take a look at the picture. Please write your answer with an explanation.

Ahat [919]

Step-by-step explanation:

what answer is needed ? the result of the calculation ?

I assume this is the case.

remember that regarding the sequence of operations brackets are first, then exponents, then "dot" operations (× and ÷), and only at the very least come the "dash" operations (+ and -).

and that a combination of - + or + - results in -.

14 + 16 ÷ 2³ - (12 + 3²) ÷ 7 + 2 × (-5) =

14 + 16 ÷ 2³ - (12 + 9) ÷ 7 - 2 × 5 =

14 + 16 ÷ 2³ - 21 ÷ 7 - 2 × 5 =

14 + 16 ÷ 8 - 21 ÷ 7 - 2 × 5 =

14 + 2 - 3 - 10 = 3

7 0

1 year ago

The ratio of cake to cookies is 1:10. If there are 60 cookies, how many cakes are there?

sesenic [268]

Answer:

there are 6 cakes if there are 60 cookies

Step-by-step explanation:

1:10

60÷10=6

1:10 (multiply both sides by 6)

6:60 there are 6 cakes

3 0

2 years ago

Plzzzzzzzzzzzz help

kupik [55]

Answer:

Step-by-step explanation:

If you look at the graph where it says 0 minutes which would be on the origin and look up, it will be at 1,000 people which means 1,000 people were there before anything started.

7 0

2 years ago

PLEASE HELP ME GUYS OR I WONT PASS this calculus!!!!

KonstantinChe [14]

Answer:

b. $\displaystyle \frac{1}{2}$

General Formulas and Concepts:

Pre-Algebra

Order of Operations: BPEMDAS

Brackets
Parenthesis
Exponents
Multiplication
Division
Addition
Subtraction

Left to Right

Algebra I

Functions
Function Notation
Exponential Rule [Rewrite]: $\displaystyle b^{-m} = \frac{1}{b^m}$
Exponential Rule [Root Rewrite]: $\displaystyle \sqrt[n]{x} = x^{\frac{1}{n}}$

Calculus

Derivatives

Derivative Notation

Basic Power Rule:

f(x) = cxⁿ
f’(x) = c·nxⁿ⁻¹

Derivative Rule [Chain Rule]: $\displaystyle \frac{d}{dx}[f(g(x))] =f'(g(x)) \cdot g'(x)$

Step-by-step explanation:

Step 1: Define

Identify

$\displaystyle H(x) = \sqrt[3]{F(x)}$

Step 2: Differentiate

Rewrite function [Exponential Rule - Root Rewrite]: $\displaystyle H(x) = [F(x)]^\bigg{\frac{1}{3}}$
Chain Rule: $\displaystyle H'(x) = \frac{d}{dx} \bigg[ [F(x)]^\bigg{\frac{1}{3}} \bigg] \cdot \frac{d}{dx}[F(x)]$
Basic Power Rule: $\displaystyle H'(x) = \frac{1}{3}[F(x)]^\bigg{\frac{1}{3} - 1} \cdot F'(x)$
Simplify: $\displaystyle H'(x) = \frac{F'(x)}{3}[F(x)]^\bigg{\frac{-2}{3}}$
Rewrite [Exponential Rule - Rewrite]: $\displaystyle H'(x) = \frac{F'(x)}{3[F(x)]^\bigg{\frac{2}{3}}}$

Step 3: Evaluate

Substitute in x [Derivative]: $\displaystyle H'(5) = \frac{F'(5)}{3[F(5)]^\bigg{\frac{2}{3}}}$
Substitute in function values: $\displaystyle H'(5) = \frac{6}{3(8)^\bigg{\frac{2}{3}}}$
Exponents: $\displaystyle H'(5) = \frac{6}{3(4)}$
Multiply: $\displaystyle H'(5) = \frac{6}{12}$
Simplify: $\displaystyle H'(5) = \frac{1}{2}$