Here you have an equilateral triangle. Because of this you know that all angles are also the same as each other. We know that the angles in an equilateral triangle are 60°.
so let's set 7x + 4 = 60
Subtract 4 from both sides: 7x = 56
Divide both sides by 7: x = 8
Is this a year 9 question and if yes I do not have a clue lol
Answer:

Step-by-step explanation:
Point Z divides XY into a 5:3 ratio, so Z is 5/3 of the way from X to Y. That ratio is k, found by writing the numerator of the ratio (5) over the sum of the numerator and the denominator (5 + 3 = 8). Our k value is 5/8. Now we will find the rise and run values which is the slope of this line segment:

Coordinates are found in this formula:

Filling that in:

which simplifies to

which gives us the final coordinates of Z to be 
To solve an equation for one variable, we will utilize PEMDAS ( parentheses, exponents, multiplication/division, add/subtract) but backwards. So we will first add/subtract any numbers to the other side to get the variable by itself. We will then divide/multiply any numbers to get the variable by itself.