Can someone please explain how to do systems of equations with substitution

1/3(x-10)=-4 solve for x with steps

Asap its important using the information in the customer order, determine the length and width of the garden. enter the dimensions.length: feetwidth: feet

Match the following reasons with the statements given to create the proof. 1. do = ob, ao = oc sas 2. doc = aob given 3. triangle cod congruent to triangle aob vertical angles are equal. 4. 1 = 2, ab = dc if two sides = and ||, then a parallelogram. 5. ab||dc if alternate interior angles =, then lines parallel. 6. abcd is a parallelogram cpcte