Solve the following system of equations. 9x + 4y = 4 -5x + 7y = 7

The solution is:

Step-by-step explanation:

We have the following equations

To solve the system multiply by the second equation and add it to the first equation

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Now substitute the value of y in any of the two equations and solve for x

The solution is:

answer: a clock

step-by-step explanation:

the answer is: d) o, f, and kr.

atomic radius of bromine (br) is 114 pm.

atomic radius of oxygen (o) is 73 pm.

atomic radius of fluorine (f) is 72 pm.

atomic radius of krypron (kr) is 112 pm.

the atomic radius of a chemical element is a measure of the size of its atom.

the atomic radius varies with increasing atomic number, but usually increases because of increasing of number of electrons.

the atomic radius decreases across the periods because an increasing number of protons, because greater attraction between the protons and electrons.